For what it's worth, OP, I didn't have kids and am now in my 60s and I don't regret it at all.
My one big chance was in my mid-30s, when I'd been with DH#1 for 15 years. The pregnancy was an accident (change of pill, protection diminished during transition) and he was furious with me, saying I'd ruined his life etc. He seemed to think I'd done it deliberately for some reason (he always blamed me for everything). I ended up having an abortion rather than have a child with someone who could be so stupid and cruel. A few years later, I left him.
In my late 30s, the question of whether to have kids or not raised its head quite a few times. I nearly did with one guy; thank god I didn't, as things would not have turned out well (he was, in retrospect, a bullying narcissistic cheat!).
Mostly, though, my focus after divorce was on making up for lost time, which meant doing anything that wasn't boring (having been bored stiff for years). Thus life became pretty wild for a time, but never dull, and I learned an enormous amount.
I'd definitely have had children if you could guarantee that things would turn out well: that they would be healthy, that we would love each other, that I could pour wisdom and kindness and humour into them in ways that they would appreciate.
It just seems to me that parent–child relationships are rarely that simple. Most of the families I know, it seems to be more a case of "Ooh, it's so lovely when things are going well, makes up for all the shit you have to put up with" 🤣 ... but maybe I just haven't seen the joyful wonder of it all close at hand, if it all happens behind closed doors.
I am not a particularly lucky person and have poor boundaries, so I tend to think that if I'd had kids, I could pretty much guarantee they'd be the sort to roll their eyes and get stroppy and create endless mess for me to clear up (literally and metaphorically).
You mention sort of an urge to make a mini tribe of people who will know that I exist.
See, I feel as though over all those years when I could have been running the kids round the M25 to tennis classes or whatever, instead I've gradually built up my own mini-tribe of people who truly value me. But they're not family. (In fact, to be honest, my family mostly treat me with contempt!)