Only in the world of fashion could the appointment of someone in their early forties be seen as a radical riposte to ageism. And in sport. And ballet. And Hollywood. And among female newsreaders and presenters . . . come to think of it, there’s an enormous disjuncture between reality – 50 per cent of Britons are 40 or over – and what is beamed back to us through the prism of popular culture.

Prada’s decision to engage Linda Evangelista, 43, for its new advertising campaign could be seen as a token gesture – and not even a new token gesture. A couple of years ago, Marc Jacobs used Charlotte Rampling, in her sixties, in his ads. Dior had Sharon Stone fronting its antiageing line – or it did before her little indiscretion about the Chinese. Evangelista has been working steadily in recent years for other commercial brands.

Then again, this is Prada, one of the most influential labels in fashion, whose choice of figurehead is nervously awaited every season by the industry. It was Prada’s support that ensured that pale, extra-skinny Eastern European models dominated fashion for the past six years – the fact that those girls never really resonated with the mainstream public, and did not become trendsetters in the way that celebrities have, suited Miuccia Prada’s purposes perfectly, helping to perpetuate the myth that this was still an insider’s label rather than a global business generating hundreds of millions of pounds a year.

Different times call for different tactics. With the It bag on the way out, the financial focus of brands is switching back to shoes, jewels and, yes, even clothes. That means finding models who can engage with customers.

So we’re back with supermodels. This season, Naomi Campbell, 38, Christie Turlington, 39, and Claudia Schiffer, 38, are pushing back the boundaries – interesting, considering that a few years ago models were pretty much done at 26. Dolce & Gabbana has gone one step farther – as it often does – and engaged the services of a beautiful septuagenarian for its “youthful” D&G line. They’ve all been airbrushed to look ageless, but we know who they are – and we know they’re not teenagers.

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