Howard Jacobson: Deliver me from these Kate Middleton clones

This being London Fashion Week, unless last week was London Fashion Week, we attend with respect to the words of Vivienne Westwood.

Everyone is wearing "disposable crap", she says; people have never looked uglier; everyone is conforming; the young are as though cloned; the only ones who look interesting are 70.

I'd add that the only ones who "say" anything interesting are 70, but that would be to extend the argument further than I think Vivienne Westwood means to take it, and further, on reflection, than I do. The generations should not disparage one another. The war between us is a phoney one. We are one another's reflections, not one another's enemies.

Some readers might think any comment on fashion from me is a comment too far, given my own taste in tailoring which, as I have never scrupled to conceal, can best be described as Prestwich and Bury post-bar mitzvah cosa nostra. But I mustn't tar the whole of north Manchester with the brush of my sartorial boldness. The little black suit – the boy equivalent to the little black dress – is all I can blame on my upbringing and environment. Always be ready for a job interview, an encounter with an older relative, or a funeral, was the philosophy behind it. The cosa nostra bit – always be ready to make someone an offer they can't refuse – is an addition all my own. High-collared Brioni shirts, double-buttoned at the neck, with gun-metal points at the cuffs, worn with two-tone protected-species shoes. If I dress like this less often than I used to that is only because I was mistaken recently in Taormina, not for Al Pacino, but for Harry Hill.

The which confessed – and anyway, the more mistakes one makes oneself, the better equipped one is to notice them in others – let's return to Vivienne Westwood's comments. That they have caused something of an outcry from fashionistas who are not themselves 70 is only to be expected. And she would have been disappointed had they done otherwise. But I recognise what she is describing, especially in the matter of cloning. Yesterday, I mistook at least five different women for the Duchess of Cambridge: the same mid-length brown hair, the same slightly pert deportment, the same brown Hobbs coat she wore on St Valentine's Day. Kids, of course, have always lacked the courage to dress outside what's demanded by their tribe, but news of those demands used to travel far more slowly so that there was always a chance you might blunder by ignorance into originality.

Now you are social-networked into an instantaneous obedience. On that same walk in the course of which I encountered five Kate Middletons, I came upon a conga line of mainly boys – all carrying skateboards and wearing backpacks and back-to-front baseball caps – waiting patiently to enter Supreme, a shop of which until then I had never heard. On making discreet enquiries, I discovered that this was one of the very few outlets for Supreme in the universe, that it had reopened with its new collection that very morning, and that it sold skateboards, backpacks and back-to-front baseball caps. I ask no questions about how these kids knew this, or were able to get off work or school in order to spend the morning queuing, but their sameness hurt my eyes. Had one of them been a child of mine, I would not have known which it was.

On the way home, I had to help up a young woman who had come crashing off her Kim Kardashian heels. I do this two or three times a day. I don't lecture them on the symbolism of the fallen woman. I don't tell them that Vivienne Westwood says they look crap. I just give them my arm and offer to escort them to the nearest A&E. It's not my job to save the world, but I feel it's the least I can do, since I am generically a man and therefore one of the reasons – I only say "one" – that women are prepared to undergo this indignity. That fashion trumps what men think I acknowledge. But that's Vivienne Westwood's point. Fashion will make a clown of whoever slavishly follows it.

Then again, though it might only be the circus or the pantomime, at least women are dressing as though for an occasion. Whereas the men you see them with are in thrall to the fashion that dictates you mustn't look as though you've dressed at all. I've seen women at the opera in ball gowns and diamond earrings escorted by men who affect the air of having just rolled out of bed, just rolled a joint and just rolled in dog hairs. When I'm not raising fallen women, I'm offering succour to men I discover shivering and apparently starving at street corners with their shirts out of their trousers and summer trainers on their feet. "Oh, should I be wearing something?" their expressions say, as I take them in my arms and warm them back to life. Sometimes I wind them in a spare scarf I carry for this very eventuality.

More fabric and lower heels is the battle cry of the over-70s. Don't knock it. There's wit in dressing sensibly. It references not dressing sensibly. But compassion for the young is called for, too. It's no fun freezing or falling over. And you can't blame them for not looking who they individually are. They don't yet know. You have to be 70 for that.