It will surely come, some day.
They're taking baby steps, but steps nonetheless. They started with Freeform shows, with shows that are a bit more aimed at adult or teen audiences. Then they went ahead and took a tiny step by having a one time only appearance by a lesbian couple on Good Luck Charlie. Then there were the rumors (which are still rumors I guess since we haven't heard any confirmation since) of a gay character in Star Wars, and I mean, there's definitely some gay undertones in some Marvel movies, especially with the whole Deadpool/Spider Man thing. Just recently there was a same-sex kiss on a cartoon Disney Chanel (or Disney XD? not sure) show, and now the news of a gay secondary character on a big live action Disney production.
So yes, I do think it will eventually get there, that a Disney Animations Studio character could belong to the LGBT spectrum. And I think we are closer to it than we used to be - but Disney, as a company, has always been very, very cautious about its stance for anything LGBT. I believe they will keep on being that way for a little while longer still.
That being said, when it does happen, I hope it's not the focus point of the story. Like... being gay isn't a plotline, so hopefully they thread carefully with how they chose to portray it. But ultimately any representation is a step forward.