There must be literally weeks if not months worth of interviews on this site, and from what I’ve looked at so far it’s a lot less superficial than you’d expect from the American chat show format.
Just put a favorite artist, political figure or musician into the search engine and if you’re lucky you’ll get nearly an hour’s worth of uninterrupted chat with them. Great recent interviews with Hitchens and Amis for example. And this gem from 1996 in which Bowie and Schnabel talk about the then just released Basquiat movie they made together:
Even as a Bowie fan I sometimes cringe at the Bowie act he switches on in interviews, but here he’s about as unaffected as I imagine he’s ever been in front of a camera.