There's nothing to apologize for, besides causing hurt. He's not going to apologize for the views he holds, or for contributing to a cause he believed in because he had the means. Even if his views have since changed, which personally I don't find relevant, people should not be expected to apologize for the views they once held, for the reasons they held those views are beyond all of us to explain or denounce. Everyone is struggling to make sense of the world, and popular opinion isn't the official stance for everyone.