i don't read pixiv fanfic so i can't say on that front but bl manga has come a long way as well! like there's def still straight AV references but also lots of characters who are strictly gay!

and i think what people find exciting in fanfic (first time/gay for you/etc) isn't necessarily reflecting what kind of stories they like in canon material, or actual original gay media, either? which, in my experience, one of the main differences is that jp audiences seem to like ambiguity more than western audiences. that's why eng fandom wants to say "this character is trans, the only way to interpret them is trans, and if you don't you're a bad person" while jp fandom is like "(character name)'s gender is just (character name)" so often lol -- the label isn't important, the character and the role they play in the story/the character archetype they're meant to play/the audience they're supposed to draw in is.

of course, this definitely can get frustrating when you're like "CAN YOU JUST SAY GAY!!!" and there IS importance to naming experiences and claiming/representing identities. some of if certainly is an aversion to decisively labeling someone (specifically as something lgbt), but i think part of it is just different approaches to the roles of characters, too.

AND THAT SAID, obviously we know homophobia is a thing and it's not paradise for lgbt people in japan (or pretty much any place). like i said, i'm def not saying there's never homophobia or discomfort about "saying gay" at play there. but i just don't think homophobia or close-mindedness is the only reason behind this kind of difference between fandoms.