The characters being ancillary and easily edited out/cut is by design so they can still use the movies in foreign markets that are hostile to lgbt rights
If the gay character is only identified as gay in one scene where they say “I’m gay” or kiss for 10 seconds you can just cut that part out and still screen it in Saudi Arabia. Disney doesn’t actually give a shit about lgbt issues, they give a shit about what will sell
Thus a prominent main character who is gay or a movie about a character coming to terms with queer identity is far less likely because that basically means they instantly lose out on much of the lucrative international market