Look I don't think gays should be allowed to marry. I don't think they should be able to adopt. I am not going to hide behind they need a mother and father growing up.
I don't think that gays are incapable of raising kids. But I do think that there is definitely a hierarchy of most optimal to least.
Something like
1)Healthy Mother and father
2)healthy single mother
3)healthy single father
4)southern mother and father
5)LGBTQXW
6)Parents in troubled areas
7)all other non optimal scenarios
15)Jews