Mission hill, a show you’ve likely never heard of, back in 1999 had two characters named Gus and Wally. They were the upstairs neighboors of the main cast though Gus and Wally did have their own episode (the show only ran for 1 season and had 13 episodes) as well as having some side plots in other episodes. Now the very first scene they’re in they are making out.
Let me repeat that, back in fucking 1999 there was an openly gay couple in an animated show who were functionally main characters. They weren’t the perfect couple, they acted like your old married coupke, but the show never once made them being gay a joke, a bad thing, or anything of the sort. They were treated respectfully as flawed humans who loved each other for the show’s entire run.