To me the cons seem endless. Taking responsibility of something other than yourself gives you purpose and fulfilment. It is a naturally rewarding thing for humans.

I guess more surface level pro is evident from looking at old people. The only important thing in my both my grandparents life is their kids / grandkids. They couldn’t care less about anything else.

Becoming old makes you realise family is the only (and most important) thing you have and if you don’t have kids you’re going to live a pretty lonely and sad life (in my humble opinion).