a lot of anime and Manga featuring gay characters are also meant to appeal to straight women because women think guy on guy is hot
there is the rare gay character that seems to have been written with an actual gay audience at least partially in mind (Yuri on ice to some extent and Bulaut in Akame ga Kill) but overall the average Japanese person feels one of 3 ways about gay people
1. they're entirely indifferent (best case scenario)
2. they think they can politely persuade gay people to not be gay by setting them up on blind dates with opposite sex people
3. they just pretend gay people aren't real
there are some people in Japan who are genuinely okay with gay people though, the anime industry however stifles those people, like Hunter X Hunter's author