Dads

I only had time to read the start, but the author's friends did not prioritize and make any time for their social lives outside their kids. You see this with highschool or college students that get their first serious relationship: they completely fall off with their friend group for months or forever.

When you start a new phase of your life it can be seductive to give it all of your time and not make room for anything else. Going to college, new job, marriage, babies, etc. And if that's what you want: great! But you owe it to the rest of your life to let them know or they'll figure it out and grow annoyed and less likely to try to reach out.

This'll be a problem when you eventually have the time to take a step back and realize you've dropped all your connections. Your friends may not want to try reconnecting with someone who had no notion of sharing any time.

Now this isn't to say a newborn doesn't demand all of your time: it absolutely does. But with today's ability to connect, it's really on you to make sure you keep occasionally connections going and you don't flood them just with your new baby or whatever. I have a friend with a 7mo old and while they dropped off a lot, we never lost contact with them via online messaging and they made a big effort to still get together. Even if it was just coming over and having delivery. Or eventually going out to baby-friendly restaurants and having longer board game nights. It can be done, you just have to prioritize it.