I've had a short stint in counselling school and have a therapist friend studying post grad and honestly, no, therapists definitely haven't heard it all. They're just regular people.

I've brought up stuff my ex T told me she's never had a client bring up before. Current T too. And yet the issues I'd brought up are common issues in my demographic and subculture but completely foreign to my therapists...despite how we're born and bred in the same small country... They both have less than 10 years experience as therapists though...