Hmm... that's an interesting point. I feel like if this guy was a CEO or someone with authority over employees, then he should resign, because he would have power over other people and his antisocial views would contribute to a less productive workplace. But if this is just a random guy helping out, just like all the other people helping out, and no one is really committed to stay with the project in the first place, then maybe the project should live or die based on whether or not people are willing to continue working with him. It's like if a charity denied a contribution from a wealthy donor because the donor is homophobic. Should the charity really care who the money comes from? That said, I'm not entirely sure what it's like working on a project like this, maybe I don't understand the dynamics.