It is a bit telling, that you perceive it as "promoting of homosexuality". I am not gay and I don't see anything like it. What I see, is promoting of a idea, that people are free to live their (consented) sexuality, whatever that might be, instead of forcing them to live an unhappy life not fitting to them. That is not really good, if you want stable people. And without stable people you won't have a stable society.

And about birth rates in general, that is a way longer debate. I would start with world population and limited ressources, but rather leave it at that.