Having kids has nothing to do with ability to maintain friendships. But after you have kids, there’s a realization that some friendships are superficial and meaningless. Sure some moms and dads are burnt out but there’s a bunch that just don’t give a fuck to talk about Netflix shows or random stuff that makes no sense. Kids become the center of your world so maintaining friendships with people that don’t have kids just loses its appeal. We have four kids and neighbors that are in their 50s with no kids. They live the most boring life and always say how they regret not having kids. Literally there’s only so much you can drink, and only so many places you can travel before it’s all meaningless. No one cares if you have kids or not but no active parent is gonna prioritize a friendship that is surface level. And if the friendship is important, it’ll be maintained.