After 25 years of providing the definitive soundtrack to Christmas parties everywhere, and just two wonderful months as the devoted face of pigs in blanket-flavoured crisps, Mariah Carey has finally hit the US No 1 spot for the very first time with All I Want for Christmas Is You. The fact that it has taken so many Christmases to get there is astonishing, given its seasonal dominance.

But All I Want for Christmas… is one of the few festive songs it is difficult to grow tired of, and I say this as someone who worked in a department store over two long Christmases, and had my ears bludgeoned by the same CD of pan-piped yuletide joy on repeat, a Santa boot stamping on the human spirit, forever.

The ubiquity of Carey, which seems to have gone into overdrive this year – never something to complain about, only to luxuriate in – has made it plain that there are no real contenders for a new classic Christmas song, and there has not been one for some time. The most recent you’ll hear out in the wild is probably the Darkness’ Christmas Time (Don’t Let the Bells End), and that came out in 2003. The fact that this coincides with the rise of Pop Idol, X Factor and other TV talent shows is not unconnected. For many years, the winner had a Christmas No 1 sewn up, though it was never a specifically festive song; they weren’t about to risk post-December sales on a track that would lose its appeal as soon as the turkey was finished. There have been charity songs and protest songs since – this year’s attempt to get Jarvis Cocker’s Running the World to No 1 really would have been a gift, if only to see if any newsreaders would have said the wonderfully crude and apt chorus line – but each year the slot loses more of its power, and there is no space for a new classic to come through.

Perhaps it’s just that the alchemy of a true Christmas hit is impossible to dissect and repeat. Carey is upbeat, joyful, irresistibly poppy; Fairytale of New York, the devil to its angel, is the saviour of the miserably drunk reconciliation; East 17’s Stay Another Day is only a Christmas song because they put sleigh bells on it and dressed up in wintery quilted jackets for the video. They have nothing in common but their sticking power.

This year is Carey’s, as it should be. But we have plenty of proper, spirited pop stars again, and it is not too late for them to have a go, next time, at the great Christmas song revival that is long overdue.

Roxanne Pallett: queen of the fake news era

When Roxanne Pallett agreed to go on Celebrity Big Brother in 2018, she must have wondered if she might emerge a winner. Last week, she became one, as the person at the centre of the most complained-about TV moment of the decade.

When she accused housemate Ryan Thomas of assaulting her, the footage, from a house full of cameras, proved otherwise, and more than 25,000 viewers were irate. There is something irrefutably late-stage celebrity-ism about the affair, which felt like a natural end to the torrid reality TV cycle begun by Jade Goody.

Elsewhere, a bruising sting by the rapper/podcaster Blindboy on his BBC Three show Blindboy Undestroys the World saw Instagram influencers Lauren Goodger, Mike Hassini and Zara Holland tricked into auditioning to promote a fake drink called Cyanora. Its crucial ingredient was hydrogen cyanide. When Brass Eye did a similar stunt in 1997, and Chris Morris had prominent figures speaking out against Cake, a fictional drug, at least they did so in the public interest. Now, influencers consider taking money to flog a poisonous chemical. We get the celebrities we deserve.

Camille Schrier: a brainy victor, but it’s still a beauty contest

Facebook Twitter Pinterest Camille Schrier: ‘to be a looker is no longer enough’. Photograph: UPI/Barcroft Media

When Camille Schrier showed off her talent during this year’s Miss America contest, it looked like a moment ripped straight from a Disney movie. The 24-year-old scientist, previously crowned Miss Virginia triumphed over 50 other competitors to be named this year’s winner, after demonstrating the catalytic decomposition of hydrogen peroxide on stage. Name a more 2019 sentence. I’ll wait.

Last year, Miss America announced that it would no longer judge contestants on their outward appearance, and scrapped the controversial swimwear round. It is now interested, it claims, in “preparing great women for the world” and “preparing the world for great women”.

Last week, the trailer was released for Misbehaviour, a British film starring Keira Knightley and Gugu Mbatha-Raw, which takes us back to 1970’s Miss World, which was disrupted by feminists.

Those protesters might not have imagined that such contests would still exist in 2019, much less as a forum for contestants to “advocate for their social impact initiatives”. While this is surely better than judging women for how well they can model a bikini, the pressure never ends: to be a looker is no longer enough, if Miss America must also now have two degrees and be studying for her PhD.

For her live experiment, Schrier poured chemicals into flasks and made three big fluffy colourful flumes of gunk. It was She’s All That, in reverse. In the 1999 teen film, Laney Boggs whips off her glasses and lets down her hair to reveal that she has always been beautiful. In Miss America, the beautiful woman put on her glasses and lab coat to reveal that she has always been smart.

• Rebecca Nicholson is an Observer columnist