I've turned down a couple of very unimpressive offers from "mainstream publishers"
I mean people may not approach a mainstream developer because they don't think their game is good enough or they think they would get an instant rejection. I am sort of trying to say people should not feel that they cannot reach out and explore.
It's the same with normal job applications. Some people have got a job that they never thought they would get in a million years - they got it because they applied and the employer liked them - they may not have had all of the required skills - the employer simply liked them or, perhaps, had another post they were suited to. However, they could only get that job by applying in the first place.