Homosexuality in other members of the YC community doesn't affect you. Their private actions don't affect their peers at all, and the fact of their attraction to the same sex doesn't preclude anyone else from participating in YC.
If you think homosexuality is wrong but you keep that to yourself and don't let it influence your business decisions, your private beliefs will also have no effect on other YC founders, and you'll be welcome in the community.
If a gay man said "I believe heterosexuality is wrong and I reserve the right to not do business with heterosexuals to keep my conscience free" they wouldn't be included because that's blatantly discriminatory.
A gay man saying "I don't want to work with people who believe my sexuality is wrong and reserve the right not to do business with me because of it" that's just a rational choice to avoid people who want to punish them for something that only matters to them and their partners.
Mutual tolerance isn't a hard concept. Tolerating others' intolerance of you is not part of it.
If you think homosexuality is wrong but you keep that to yourself and don't let it influence your business decisions, your private beliefs will also have no effect on other YC founders, and you'll be welcome in the community.
If a gay man said "I believe heterosexuality is wrong and I reserve the right to not do business with heterosexuals to keep my conscience free" they wouldn't be included because that's blatantly discriminatory.
A gay man saying "I don't want to work with people who believe my sexuality is wrong and reserve the right not to do business with me because of it" that's just a rational choice to avoid people who want to punish them for something that only matters to them and their partners.
Mutual tolerance isn't a hard concept. Tolerating others' intolerance of you is not part of it.