Thing thing about celebrities is that they tend all have the same friends in some way and those connections is what ends up landing you jobs and stuff. You go to a party, you meet a producer, you suck his dick, the producer gets you a job. Then you meet a bunch of people on set, mingle there, go to a party, suck some more dick and get more jobs and so on.
I mean, a huge part of this stuff isn't even quid quo pro casting couch stuff, its literally just people meeting at parties, having sex and getting to know each other and wanting to work with each other because they get along socially. A huge thing about the gay community is that they all tended to hang out in secret and everything was very hush hush because you weren't allowed to be gay back then. Some would dress up in costumes at orgies so that you couldn't get outed and so on. From an outsiders perspective it might seem like some crazy illuminati shit because people might go to great length to preserve the image as a heterosexual or a modest woman or a married man but tons of times it was just straight up faked marriages, closeted homos and high end prostitutes posing an actors all over the place.
Really, once you look behind the veil its really just very "Oh, so its just people fucking...damn. I thought there was at least gonna be some magic ritual cult stuff going on."