It's common in some tech and upper middle class bubbles, but outside of some startups and a few VHCOL cities most of the 40+ people in tech I encounter have families.
I think the mindset is most popular in internet bubbles like Reddit. Reddit went mainstream a decade ago and many people in their 30s and 40s grew up reading a lot of Reddit. Reddit cleaned up their popular subreddits list years ago, but for a while subreddits like r/childfree were constantly in everyone's default feeds. Redditors would talk about people who had kids as "breeders" as a derogatory term and treat them like they'd made terrible decisions with their lives.
I didn't realize how much this carried over into the real world until my friends and I started having kids. I knew a few people who treated our decisions like we were making terrible mistakes and throwing our lives away. I still encounter people from younger generations who are confused when I say that I like spending time with my kids. They can't imagine how that would be enjoyable in any way. When you grow up with your chosen social media telling you that the smart people are maximizing their bank accounts, minimizing their responsibilities, and doing as little as possible to get there, they can't fathom how someone could be happy with kids.
This describes all of the childless people age 50 and older than I know.
It does not describe the social media r/childfree mindset people I know at all. They have their bubble of friends they keep in touch with only when they feel like it but that's about it.
There's a big difference between childless and r/childfree style people, though.
> People wanting FIRE is a lot more to do with the current economy and wealth of useless or harmful jobs than kids
FIRE rose to popularity before this economy, though. It felt like peak FIRE was during ZIRP when it was easy to get a high paying tech job even if you barely had the skills for it. All the blogs and influencers made it sound so easy to just keep that going straight into early retirement as long as you continued living an austere lifestyle, which came with implied advice to avoid having kids.
I followed several of the FIRE blogs and forums in the early days but had to stop reading after they started filling up with people convinced they could retire at age 36 with $1.2 million in the bank because they they lived frugally last year and decided they could keep coasting that way for another 50 years without their lifestyle changing. I remember reading a few disaster stories from people who thought they were doing leanFIRE with their spouse until their spouse grew up and realized they actually wanted kids and to be married to someone who had a little more ambition in life. I know these stories aren't what FIRE is supposed to be about in the theoretical optimal sense, but there were so many stories like this that the forums just felt like a sad place to be.
On the other hand it remains quite confusing that after centuries of capital achieving vastly better results than labour people still keep going for labouring as their primary strategy. Building up a strong income-generating capital base is just common sense and it is an extremely good idea to have enough that you could technically avoid working if it made sense.
Someone has to bring up the next generation, the no kids crowd want all the luxury of having the next generation without putting in the effort or spending the money.
We have no shortage of humans, so there's no need to try to shame the childless. Nor those who focus on themselves.
You got lucky and had kid(s) that were not extremely difficult to raise. Not everybody gets that. Not all kids are alike. Some will make your life a living hell. It is a total crapshoot.
Also, not everybody enjoys parenting, even if they have easy kids. We are not all built the same.
I did get lucky and had relatively easy kids. I love them. But, I do not enjoy parenting.
I love my kids and they're pretty great (and seem easy by comparison to others), but it's definitely burdensome and hard.
People can obviously make the opposite choice, but I'd encourage anyone that's never been around good little kids as an adult, to find a way to be around them in a helpful or fun role for a while. Volunteer at a youth group, sports camp, coding class, whatever. Or just be an "uncle" to some of your friends' kids. My volunteering at a church youth group in my early 20's probably gave me the nudge I needed.
Candidly, if half of your friends are in regretful marriages and 90% of the people you encounter are "crap" then I would be questioning your social filtering.
This is a strawman position in my opinion. I don't think there's that many people who think they're carrying out some selfless act by having children. It's simply biologically true that the children you'll probably have the easiest time raising are your own and, assuming we want to continue as a species, we do need people to have children. It's fine to have them, fine to not, neither side has some moral high ground.
The thing I most crucially remember about my son being born is that it felt downright easy to simply dive into all the things I would now be doing: because there was no one else. I either got it done or it didn't get done.
Someone else's kids on the other hand there is a choice: their parents.
It's not absolute IMO but you also see it echoed by working too: when it's your job, it's a lot easier to simply go "right I need to handle this" then when it's not.