Fyi, desegregation and decriminalization of SSM have also both happened under a mostly Christian society. I don't think it was because an atheist cabal took over (unless you are intellectually in camp with the extreme fundamentalists, they might say that). Under what special mode of reasoning do you get to credit the Christians who accepted these rules and not the Christians who fought against them?
It used to be abolitionists who were the crazy extremists. What did they typically cite as their reason for advocating those extreme beliefs?
Otherwise, what rational reason is there to deny other people their own choices in how to live their lives as long as they aren't victimizing anyone?
Right, the only motivation anyone has for wanting society to go along with their ideas is religion. That's why we have people who want to ban you from ordering a large soda, smoking a cigarette, homeschooling your kids, using gender pronouns, etc.
There are plenty of societies which have realized religious beliefs are a problem and have restricted them. Which of those do you find more free and preferable to the one you live in right now?