Even rating the cover alone gives strong hints at the story being all about activism, which means it's driving people away from it.

"But Oniichan wa Oshimai is a really good tranny manga/anime!"
There's a difference though.
Onimai has a character that is part of the greater comedy, and there's no "oppression" or any other politics in it, which is OK.

LGBT activists on the other hand tend to be all about the character with barely any story telling if at all, and it's nothing but politics, which is NG.

This is why there's 1 good Japanese TSF (there are many more, but for the sake of this post I'll keep it to 1) that people actually like, and thousands of garbage western TSFs that nobody wants.