Maybe this is just an online thing? IRL I hang out with quite a few Marxist-Leninists, Maoists, and other folks who'd usually get categorized as tankies and I don't think I've heard them be bigoted towards queer people during the years I've known them. I'm also openly queer so it's not like I'm just an "ally" saying that they don't see bigotry happening just because they ignore it.
These same folks are also organizing most of the pride events around here and running volunteer security for protests and drag shows, so I'd have a hard time believing that they're secretly bigoted while spending a lot of their time, money, and taking personal risks to foster a queer community and keep it safe.
I'm sure it'll be hilarious when I explain to my co-organizers that the Stalinist in our group isn't a tankie because they support LGBTQ+ rights