I'm sort of getting the impression that homosexuals try not to hit on someone unless they know they are bi/homosexual (is that right?), but I've had great luck with randoms.

I've noticed this too but have never discussed it with anyone, so it's fascinating to consider the possibility of it being a legitimate trend. I have no idea if this is a thing with gay men, but it seems like the majority of lesbians have a low tolerance for ambiguity in these matters, combined with what appears to be a strangely low level of trust in their own ability to read others' sexuality and degree of attraction. I do understand why a person would want to avoid developing a crush on a false positive, but I've always found it strange that lesbians seem to have such poor gaydar, or such little faith in their gaydar.

Anyway, I'm gay but I'm like you: most of the women I've had big feelings for have been randoms, and I'd much prefer to just feel things out in the wild than use a dating app. The whole ambiguity aversion thing actually makes me feel pretty alienated from most lesbians, but that's another story.

Edit: this might just be a female-typical trait that lies dormant in straight women in the proto-dating phase since men are a bit easier to read and since it's understood that OSA men are so plentiful. I don't know.