I'm in favour of encouraging bright young new playwrights, but I hate to see the waste of bright old playwrights. I don't mean the thirtysomethings who have recently been complaining that they are losing out to the twentysomethings. I mean the baby boomers, the folk who saw 1968 come and go, and know everything there is to know, from the secrets of the universe to the correct way to roll a joint (which they would never dream of calling a spliff). Let's cut to the chase here – sixtysomethings like myself, launching new careers after quite a few decades of doing other things.

Novelists and their publishers manage these things much better. Marina Lewycka published her first novel, the hysterically funny A Short History of Tractors in Ukrainian, at the age of 58. Three more novels from her have shown this was no flash in the pan. My old journalist friend Wendy Wallace's first novel, The Painted Bridge, is out in May, and if the quality of her reportage is anything to go by, it will at least be powerfully written. I know two other fiftysomethings with new novels on their way from prestigious publishers.

Yet the older playwrights of whom you have heard made their reputation in the 70s or even earlier. Is this because of the relative youth of the men and women who run new writing venues? I have noticed an instinct to speak to me loudly and clearly (rather appreciated, actually, as my hearing seems not to be quite what it was.) But I don't think that's the main reason.

Is it that we don't speak to the concerns of youth? We're probably a bit less uninhibited in our approach to sexual and lavatorial humour, because we saw the age of so-called alternative comedy through world-weary eyes, and saw its desire to shock as an excuse for the tameness of its political content. But our concerns are often those of youth.

My latest play, The London Spring, imagines London after a few more years of inequality, economic decline and neoliberal government, in which Londoners are reduced to begging in the streets from wealthy foreign tourists. It speaks to contemporary concerns in a way that a lot of work by younger writers doesn't.

I think much of the blame lies with master's degrees in playwriting. Far more often than not, emerging young playwrights come out of these, most often the pioneering course started in Birmingham by David Edgar. This is hardly surprising. The qualification is reassuring to a management taking a risk on an untried writer, and the teachers are well plugged into theatre managements.

When I started work on plays, nearly two decades ago, I thought of doing the Birmingham course, but I had small children then. There were the fees, and they insisted you did it full-time. I did evening classes at London's City Lit instead. Very good they were too, but nothing like as well-connected.

It's at least arguable that these MA courses have established a stranglehold over the craft of playwriting; and that this will, in the long run, damage not just the variety of writers, but the variety of the writing.