You hit on a lot of good points. I think you are missing the relationship recession in intimate relationships, which is happening around the world in non-poverty areas. Even if people are fucking, they don't really want a relationship with the person they are fucking, let alone a kid.

I live in a community with a lot of pet owners, so I found your comment pretty funny. Yes, people definitely prefer their pet over people which kind of precludes the close intimate relationships that lead to child rearing.

I would not attribute the lack of children to hedonism and materialism, but I am sure some people could be influenced by this. I think most of it is just a lack of connection with others. I am definitely guilty of not having many friends anymore. I am very friendly and helpful to people, but maintaining long term friendships outside my family is tenuous at best.