The reach for this article and FLYING misconceptions. They didn't say they were against same-sex marriage. The bug caused a problem that wouldn't let some parts of the game continue and cause errors. They never allow same-sex marriage in games because their target audience is still mostly children. Its a business thing, not a human rights issue.
And Birdo is trans* in Japan, and its here in America where they try to change who she really is. Its another Poison type situation