Like you said GL communities are really hard to find, and when I do find them can sometimes be really disappointing because it's mostly guys into loli smut. The places I actually find the most GL fans is LGBT+ sites and discords (some of which are closed groups because LGBT+ laws are different depending on country) pretty much everyone there is looking for stories with LGBT+ content, so of course the more popular sub categories for it like BL and GL will come up (even if a lot of them don't like most BL or GL, they'll honestly take whatever they can get)
Aside from online communities I know most in irl.
Complaining about tapas is VERY common in both circles, but that's very likely because I'm there and introduced most of them to the site since my own work is on here. A lot of them didn't even realize you could post non BL or straight romance comics on here, and a lot of this misunderstanding has to do with the lack of genre tag too.
To people outside of the community, the lack of GL genre isn't due to 'lack of demand' they don't know the community, they don't work for the site, they don't see the 'demand numbers' they just see that the GL genre is not there and to them it means there is no GL here or GL is not welcome.