It's a community for people who want to commune with similar-minded people, actually. That encompasses a wide spectrum, including people who simply don't want kids of their own, right up to antinatalists, but notably not people who have or want kids of their own.

Trying to convince everyone else that they must make the same decision as you comes off very insecure.

No one's doing any of that. If we were trying to convince other people this would be posted in a parenting community, not in a childfree community whose members are already on board with the idea.