There were and are many more people involved in the arts who are not gay than who are, and gay people have family and friends outside their professional world. But, yeah, just go ahead and jump to the nearest convenient stereotype, mmm?

That said, average gay participation was definitely higher at that time, which, I (totally straight, btw) always thought made it more likely we as a group would have a better idea, given all the personal connections to the homophobic, the seriously closetted et alia of the underlying reality. I stand by that assessment.