He has a large say in the benefits and culture of the company he's going to be running. If he doesn't believe gay people should have all the rights and protections of straight people, how are they supposed to feel about the future of their benefits and culture of the company they work for?
Also, it's not about "not liking the gays". It's about things like letting gay partners have the same rights in medical cases of their spouses as straight spouses. It's about child custody, death benefits, and lots of other very important things that may not be a war in Uganda but they are massively important and life-changing for the people involved.