The radio presenter dubbed the current state of light entertainment, with what she said was the constant recycling of old formats, "depressing".
Purves, who presents Midweek on Radio 4, told Radio Times magazine that TV executives relied on the same famous faces.
"One of the depressing things about TV light entertainment commissioning is its timidity. Need a new show, quiz or host? Find one who's already famous, albeit a bit tired, working too hard, spread too thin, and wave a contract," she said.
"Can't get Graham Norton, Jonathan Ross or Stephen Fry? Panic! Trawl the schedules for someone else who's already there. Want a new comedy? Model it on an old one, chaps in a flat, that sort of thing, but with funky titles and more swearing."
TV executives gather later this month for the annual Edinburgh International Television Festival, which coincides with the end of the Fringe. Purves said that if commissioners saw some of the productions at Edinburgh's Fringe, they would find the next big thing.
"Just down the road from these anxious (TV) people there's a crazy richness of discoverable talent."