As compelling as it has often been, the Leveson inquiry hasn't really told us anything new about the celebrity news game. Celebrities use their wealth to try to suppress embarrassing stories about themselves; the paparazzi hassle famous people constantly, often to the point of harassment; some editors bully and cajole celebs into giving them stories; certain reporters lie, cheat and cut corners; there is a generic pin number you can use to access other people's voicemail messages if they haven't reset it; Hugh Grant is awesome. All of this (with the definite exception of the last one) is stuff people knew or strongly suspected already. Tales of reporters going through celebrity rubbish bins are so familiar they are cliched. And it's been 11 years since a pap was found hiding inside the organ at Madonna and Guy Ritchie's son's christening venue, having spent the previous 24 hours defecating into a bin bag in order to remain undetected.

So it's not like the public thought the celebrity scandals they devoured every week were simply the results of a few polite inquiries made by methodical hacks to helpful publicists. They knew – we all knew – how certain elements of the tabloid press rolled. They just tried not to dwell on it while reading the papers over Sunday breakfast.

In that sense, it is similar to last year's MPs' expenses scandal: much of the surprise has been synthetic. MPs diddling their receipts, just like hacks "monstering" celebs, is one of those things we always had an inkling was commonplace. We just turned a blind eye. But 2011 was the year when turning a blind eye became increasingly difficult.

It is unclear what practical action Leveson might deem necessary to take against the celebrity news media. But any legislative reform is unlikely to have as much impact as the cultural shift that the inquiry is helping to bring about. This lengthy process has made it impossible for many consumers of celebrity media to suspend their disbelief any longer. The sheer relentlessness with which the ugly details of certain tabloid reporting techniques have been drip-fed by the inquiry has forced the issue to the forefront of the public consciousness. Perceptions of celebrity culture are being altered sufficiently to make a significant and lasting commercial impact.

And public perception is pretty much the only thing that can make a real difference to the way in which celebrity gossip is reported. The existing laws can't: the super-injunction scandals of last spring proved that. By attempting to go through the courts to suppress stories about their private lives, celebrities only served to make those stories bigger, more powerful and twice as likely to leak online. Celebrities with a gripe can always sue for libel, defamation, lies or what have you. But for nine out of 10 stars the process is often too costly, both in terms of money and career prospects. Besides, as Steve Coogan pointed out to the inquiry, disputed front-page splashes are usually, at best, apologised for in 100 inconspicuous words in the bottom corner of the letters page. Meanwhile, the Press Complaints Commission hovers around the fringes of the whole mess like an ineffectual supply teacher at a playground gang-fight, politely asking the knife-wielding combatants to adhere to Queensberry rules.

But editors are acutely sensitive and obsessively responsive to changing demand among their readers. And while the Leveson inquiry might not be enough to halt all demand for celebrity scandal, it might just do enough to alienate a key demographic from the sector.

There has always been a hardcore of celebrity gossip consumers who devour that stuff with a sincere relish. But the golden age of celebrity culture in the noughties was dependent on the growth of a new constituency: the "soft" celebrity consumer. This was the generation of smart, largely female, often middle-class readers who slipped a copy of the News of the World inside their Sunday broadsheet and grinned about their weekly gossip-magazine habit. Theirs was a tongue-in-cheek, slightly ironic fascination with the colourful and absurd celebrity circus. They became the large minority of the market who, by supplementing more diehard celebrity news obsessives, created a critical mass that made celebrity publishing a multimillion-pound business.

That demographic had already started to drift away from the newsstand in recent years, as commercial pressures forced much of the celeb media to abandon the fun, irreverent brand of reporting and resort increasingly to straight-between-the-eyes scandal. But this year has accelerated the process: squishing the faces of these amateur celeb-lovers in a vice and some eyelid-clamps and forcing them to confront the dark realities of the gossip trade they have been supporting. Of course, not all of that trade is culpable, but the wrongdoing of a small group of hacks has caused a ripple effect.

It is akin to a meat-eater going on a tour of an abattoir: you already knew what went on in those places, but now you've seen it, you may never be able to eat a sausage again.

The upshot is that celebrity gossip is fast losing its disarming veneer of innocent frivolity. Many people who used to brandish their celeb weekly as a badge of good-humoured ordinariness are now too ashamed to do so. It's a shame for the numerous enjoyable celebrity weeklies (such as Heat, Closer and Grazia) that remain largely harmless fanzines. But there it is. The commercial repercussions of this are significant enough to shut certain titles down for good and alter the ways that others go about their business in the future.

Celebrity faces will always dominate the newsstand. Famous types still have too much to gain from a reciprocal relationship with the press (this is probably why you haven't seen the stars with the real stories to tell – Victoria Beckham, Cheryl Cole and Lily Allen – at the Leveson inquiry). But what now seems certain is a shift towards a more reserved brand of celebrity coverage across all print media. This is something the market has already displayed an appetite for: Hello! magazine, with its slightly old-fashioned, reverential and altogether more PR-endorsed flavour of celebrity news, has been almost the only weekly gossip magazine to defy a general downturn in sales over the past couple of years (it was the only celebrity weekly to actually increase sales over the past year, by an impressive 26.8%). Brace yourselves. By 2013, every title on the newsstand may well feature a gushing profile of Nancy Dell'Olio, lounging on a chaise longue "inside her beautiful home".

Sam Delaney is a former editor of Heat magazine