GitHub is a corporation. The Opal open source project is not. The maintainers in that thread who side against the "SJWs" still readily acknowledge that corporations have different obligations to political correctness than open source projects do. Lest we forget that even if you disagree with this, the maintainers also agree that somebody's personal beliefs are not relevant to whether their contributions are acceptable. So, why should it matter that they hired Coraline, exactly? Either they have an obligation to be politically correct as a VC-funded startup that needs to ensure its public face is immaculate, or Coraline is a fantastic Ruby developer who is good at building community management tools and her politics are irrelevant.