"The secret's out," it begins, "the nation's guiltiest pleasure is one hit wonder 'Mambo No. 5' by Lou Bega." In this passage, from the teasing intimation of some great scoop to the sentence's final payoff, lurks already a kind of bathos, or the promise of high farce.

There is actually something quite perfect about the latest emission from Spotify HQ (by way of M&C Saatchi PR), in as much as its headline-hungry prose, its daubing of statistics and 'big' data, its dubious psychologism – even going so far as to quote a neuroscience professor from the University of Groningen for "insight" – ticks off so many clichés as to become almost the parody of a contemporary press release. One is apt to wonder whether the whole sheet was composed by some shrewd algorithm. Like the peculiar grammar of Twitter bots, it becomes comic, even charming. Saatchi have achieved here the seemingly impossible. They have camped the very format of a PR statement.

The perfection, of course, lies in the circularity. The form is a perfect match to its content. My instant affection for this press release is itself a guilty pleasure. In my head I am already drafting a follow-up press release in which I quote a leading cognitive scientist to explain why 74.6% of all journalists will feel the same delightful mixture of shame and titillation at Saatchi's emails above all others.

But did anyone really need Spotify to analyse 120,000 playlists labeled 'guilty pleasures' in order to at least hazard a guess that any resulting rundown would stand a fair shake of containing 'Wake Me Up Before You Go-Go' and 'Never Gonna Give You Up'? By now, a decade after DJ Sean Rowley first revealed his affection for the Alessi Brothers' 1977 hit 'Oh Lori' on Radio London, the Guilty Pleasures brand has become as immediately recognisable, as ossified and predictable, as… well, as a press release from M&C Saatchi. Even before the club nights, the compilation CDs, the radio show that started it all, we knew what to expect. Here was a beast whose features were familiar.

Half a century ago Susan Sontag already recognised the dangers in being overly serious about camp – and the 'guilty pleasure' genre-slash-industry is undoubtedly a related species or modern descendent to what Sontag identified as 'camp' in her famous Partisan Review essay of 1964. "One runs the risk of having, oneself, produced a very inferior piece of Camp," she wrote then. She defended herself with the plea of "self-edification" along with what she called the "goad of a sharp conflict in my own sensibility." Like Sontag, I too have been "strongly drawn to Camp" - and, indeed, to the 'guilty pleasure' - "and almost as strongly offended by it."

As a student at the turn of the century, I would often find myself at what were then called 'cheese' nights. I hated the concept – hated the word cheese as a descriptor for music – but in comparison to the available alternatives, I also knew I was far more likely to hear some of the music that still comprises a fair proportion of what I like (disco, synthpop, novelty records…) there rather than anywhere else. There probably was some attendant guilt involved – but it arose more from this tag 'cheese' than the actual music itself.

By the time Guilty Pleasures came along a few years later, I knew what to expect and knew that I would like a lot of it. But I no longer felt like I could actually attend such an event. Why not own your pleasures? I thought. Why this guilt? It was distasteful. An odd time for Catholicism's archaic heritage to creep back into musical discourse. The club nights were successful partly, of course, because of the visibility of the brand itself and everything I didn't like about it. But also because they were playing music that was immediately pleasurable. This was physical, bodily music; great for dancing. Hence, according to an equation older even than camp itself, a source of guilt.

Sontag detects camp as far back as the mannerism of Pontormo and Caravaggio. But its first "great period", she says, was in the late 17th and early 18th centuries: rococo, les précieux, Alexander Pope, and, a little later, the beginnings of gothic literature and the galant style in music. Only with the decorative curlicues of the Art Nouveau and the celebrated "wits" of the gilded age, like Oscar Wilde and Ronald Firbank, does the sensibility finally emerge "full-blown", however, complete with its own "conscious ideologists".

For Sontag, 'Camp' was a "a vision of the world in terms of style – but a particular kind of style. It is the love of the exaggerated, the 'off,' of things-being-what-they-are-not." "Camp," she wrote, "sees everything in quotation marks." And the "ultimate Camp statement" she finally concluded, was to say, "it's good because it's awful."

We can still recognise something like our contemporary guilty pleasures in amongst Sontag's 'Notes on "Camp"': Flash Gordon and feather boas, "stag movies seen without lust". But the critic knew well that "the canon of Camp can change." They were changing dramatically even as she wrote.

In 1964, Andy Warhol exhibited his American Supermarket at Paul Bianchini's New York gallery, enshrining a camp precept formulated by Wilde but hitherto under-appreciated – what Sontag calls "the equivalence of all objects". Kenneth Anger's Scorpio Rising, with its fetishised images of bikers overlaid with a soundtrack of Spector pop, was attracting the attention of critics. The Beatles had just come to America. This last is significant because Sontag notes, "In the last two years, popular music (post rock-'n'-roll, what the French call yé yé) has been annexed [by camp]."

If today you were to refer to the early hits of The Beatles (or of Tamla/Motown or Françoise Hardy, for instance) as guilty pleasures  – or even as 'camp' – people would think you were insane. Part of the reason for this is that three years later, Rolling Stone commenced publication and a Yale dropout named Richard Meltzer joined the staff at the fledgling Crawdaddy! magazine (in the same year, François Truffaut published his book-length interview with Alfred Hitchcock). Between Rolling Stone and Crawdaddy! - in particular Meltzer's articles and his book The Aesthetics Of Rock - popular music would become established as a serious object of study and appreciation using a vocabulary largely imported wholesale from the language of 19th century classical music criticism. Film critics like Truffaut in France and Pauline Kael in America were performing a similar service on behalf of popular cinema by the likes of Huston, Hitchcock, and Lubitsch (all of whom are referenced in 'Notes on "Camp"').

Reading Sontag's essay today, it is clear that at the time she was writing there was still a proper sphere of high art and a proper focus of critical attention. There remained works which could not "be taken altogether seriously" even if they took themselves so. By the end of the 60s, this would be much less clear.

Arguably this is a cyclical motion, and all the likes of Meltzer achieved was to apply what Sontag called the "moralistic" sensibility of high art to its own outside - creating, in the process, a new outside of the non-serious. So the sort of 'classic' rock that had featured heavily in the pages of Crawdaddy! and Rolling Stone became worthy of consideration as 'great works' while Boney M, say, or The Human League were not. In the 90s, 'Daddy Cool' and 'Don't You Want Me' were definitely still 'cheese', but perhaps today they would no longer be 'guilty pleasures'.

If the partisans of camp, cheese, or guilt-ridden pleasure have in some sense been a vanguard here in enlarging the sphere of the worthy, I can recognise an analogous process in my own biography. There have been many records and many artists that I once mocked only to later accept them as fine music. Retrospectively, I can see that the period of piss-taking was a part of the process of acceptance and taste-broadening.

Which brings us to the surprising conclusion that the sphere of the kitsch must be shrinking, as more and more stuff becomes at least potentially something like 'art' – quite the opposite of Sontag's expectation that "the process of ageing or deterioration" could provide the "necessary detachment" for a camp appreciation. Perhaps this is because the camp sensibility that Sontag regarded as marginal in the early 60s now is mainstream culture (thanks in part to the likes of Warhol and Anger). Isn't the arch detachment, the recognition that "'sincerity' is not enough", the "victory of 'style' over 'content', 'aesthetics' over 'morality', of irony over tragedy", the "theatricalisation of experience" – aren't all these tropes now our common property?

In which case, arguably, the conceit of Guilty Pleasures is to reintroduce a specious morality into what was once 'low culture' at a time when even 'high culture' is appreciated as pure style.

And yet, in the final analysis, I don't really buy this. Had I attended those Guilty Pleasures clubs of the mid-00s, I feel fairly sure I would not have seen dancers looking shame-faced and furtive. The people who make public Spotify playlists labelled 'Guilty Pleasures' are not hiding some secret predilection from prying eyes – they are making a very public declaration. They're not stupid. They know this. "Camp is generous," wrote Sontag. "It wants to enjoy. It only seems like malice, cynicism (or, if it is cynicism, it's not a ruthless but a sweet cynicism.)"

"Camp taste doesn't propose that it is in bad taste to be serious; it doesn't sneer at someone who succeeds in being seriously dramatic. What it does is to find success in certain passionate failures." Whether that involves punching the air to 'Don't Stop Believing' or cherishing Greta Garbo not in spite but because her performances lack depth, this sounds to me like a wholly laudable aim.