Susan Boyle’s Warholian quota of fame has run to 15 days now with no obvious sign of diminution. This week’s revelations include a vague family connection with David Frost; a name check on the satirical cartoon South Park; the acquisition of a faux leather jacket from Primark and — most controversially — an encounter with a bottle of Garnier Nutrisse and a pair of tweezers.

Given that everybody from CNN to the West Lothian Courier have dispatched teams of reporters to pick over every aspect of her existence but have yet to uncover her secret life as a pole dancer, it seems safe to assume that with Boyle, as with Ronseal, what you see is what you get — a doughty, stout woman who can sing.

The truly surprising aspect of Boyle is not her voice, her looks or her chastity, but her age. When did you last see a 47-year-old woman perform on mainstream, primetime television? Boyle may be two years younger than Simon Cowell but, like dogs, women on television are assumed to age seven years for every one outside the telly-bubble. Such is the demographic of Britain’s Got Talent, that when Boyle walked on stage, you’d have thought Methuselah had made an entrance.

With the innermost thoughts of Pebbles the cat laid bare and the garden fence mended, there can be few Boyle revelations left to expose. Discussion has now focused on the inevitable backlash. How will she cope when the whole circus moves on?

I should have thought remarkably well. Boyle is a woman who has nursed her mother through illness and recovered from a bereavement that left her so grief-stricken she didn’t sing for two years. Supported by a large, close-knit family and church community, she appears comfortable in her Botox-free skin. It seems unlikely the callowness of Cowell or the antics of Ant and Dec will reduce her to a blancmange of self-doubt.

Her stated ambitions are to perform before a large audience and to launch a professional singing career. With more than 100m hits on her YouTube video, she has already achieved the former. Now signed to Cowell’s music label, the latter is as good as in the bag.

Given that television likes to portray itself as a cutting-edge medium, it is remarkable how slowly it catches on to trends. For a decade we had to endure broadcasting dominated by the brittle ignorance of Ulrika Jonsson, Denise Van Outen and Zoë Ball. Perfectly presentable female newscasters were sacked or sent to the great sofa in the Sky when they reached the age of 35.

Television, whose strength had been that it was a leveller of the generational divide, became a noisy, babbly crèche peopled by kidults. Families, which once sat down together to watch the Generation Game or Ask the Family, became divided by their viewing habits as the level of inanity in mainstream television was ratcheted up to a level unbearable to the over 25s.

The three great socio-political obsessions of the age — the recession, the obesity crisis and the ageing population — may sound the death knell for the National Health Service, but they have toppled the tyranny to which British women have been subject for so long. Boyle is the double-chinned face of a generation of women made invisible by television.

The death of Jade Goody was the end of a celebrity era. Amy Winehouse is not a latter-day Billie Holiday tortured for her art, but silly, self-destructive and pathetic. We no longer care about the soap opera that is Kerry Katona’s life. Were Kate Moss to be caught on camera snorting cocaine now, I doubt quite so many brands would be falling over themselves to bag a bit of her. Gordon Brown’s mantra of “serious people for serious times” may have fallen flat at Westminster, but it has filtered down to the lower echelons of Hello! magazine.

Television executives haven’t quite cottoned on to the fact that we are sick of the shallow, narcissistic neurosis which goes with youthful beauty. The vigour of the Cameroonians — such an asset 18 months ago — now looks like callow inexperience. Michelle Obama, 45, is the poster woman for an ageing western civilisation. If Martin Amis is right and the class war has been replaced with a battle of the ages, then 40-something women appear to be winning it.

In a week in which the Queen turned 83 and Japan’s oldest pornographic movie star, the 75-year-old Shigeo Tokuda, was hailed as an inspiration to the elderly, age barriers appear to be falling with the velocity of Sir Fred Goodwin’s credibility. Stupidity is no longer fashionable. The recession has pushed student numbers up by almost 10%. We all have an opinion on quantitative easing.

And while few outside of the confectionary industry are celebrating the obesity crisis, there is no doubt that big girls are challenging our notions of normality. Fashion designers, who balked at dressing anybody above an 8, have been forced to add bigger sizes to their ranges. We may not see Dawn French in Louis Vuitton any time soon, but television is no longer the preserve of super-skinnies.

The reason Susan Boyle has had the effect she has is because she chimes, not just with her accompanist, but with the zeitgeist. She is the pin-up girl for an older, fatter, poorer nation.

gillian.bowditch@sunday-times.co.uk

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