"I just want a friend, not a gay relationship" is a fair complaint I think. That goes for the female party members you just want to be friends with too. It's legitimately annoying how aggressive most of the non-flippant dialogue options are with all the members of your team, a tightrope walk to avoid either expressing sexual interest or them expressing interest in you. I just want to hear their stories and be a supportive team leader, basically. Talk to any of them though and next thing you know you have a lot of sexual dialogue options or a harsh rejection option. I've stopped interacting with the party members a lot of the time because it gets tiring.
I think it's fine for someone like Astarion to keep making advances and innuendo after you tell him you're not interested, since he's a deviant vampire, part of his character traits, but people like Gale, Wyll, Halsin, etc., it doesn't really make sense there. There are too many ambiguous dialogue options, too. Like you choose "cheers, *raise glass*" and that's supposed to mean "let's bang" apparently, and you have to then de-escalate awkwardly. Would really prefer clearer boundaries.