But but the gay penguins in the Central Park Zoo proved it was natural and good.
Those very same penguins also abandoned their same-sex 'partners' once females were introduced to their enviroment. Up to that point, those male penguins were raised in isolation among other males, and, given that they are birds, did what birds do at a certain age and that is pair bond. They pair bonded with the available population, who happened to all be male.
Females were introduced and the majority of those same male penguins opted to form new pair bonds and to successfully reproduce with available females.