Firstly, while it's currently only got girls in it, they state that they literally plan to add FUTANARI to the game. That's not exactly completely "straight".
Secondly, there's literally no downside to adding a Male toggle or alt to the characters, because it's a wider appeal to more people = more patreons.
Thirdly, there's not really any good gay Minecraft NSFW games anyway. None that are free, this is the best Minecraft one that I've seen in general that's both actively updated and high quality.