A gay president can't be any worse than the ones we have had the last fifty years...
Until recent years, most homosexuals had discretion. They told people of their desire to take it in the caboose on a "need to know" basis.
In fact that the whole problem with Homo History. People didn't openly publicize their sexual practices, so its only a guess as to who was into sodomy and who wasn't.
Further, accusations of Sexual Perversion was often made posthumously to denigrate their political enemies. The "fact" that Catherine the Great died during an act of bestiality is highly disputed and was likely made up.