Kids are expensive and housing is intractable where the mid-level jobs are. In some housing markets, a family with 2 boys and 2 girls earning $150K/yr will qualify for government subsidized housing. It's not 1995 anymore and not everywhere is the suburban midwest.
Poverty line for a single person in San Fran is $80k/year.
In pretty much any flyover state 80k a year is decent, and somewhere like Rural Kentucky, will put you into a fairly nice house. I know folks who took a big pay cut to work remotely so they could leave NoVA and head to KY. They could get a sizable house for ~$290k (and they're from KY / have fam around, a big selling point) and basically as much land as they're comfortable with.
And to the parent poster's point, kids definitely change the equation. Not even talking things like private schools or fancy sports, just simple stuff like diapers, or replacing a torn backpack cuz Jr. decided he likes swinging it around as he walks home. And braces, jeez.
Boston's income-restricted housing program is available up to 150% AMI, and 100% AMI is a pretty common cutoff. A 6 person household with $150K is 90% AMI. In fact, even $200K at 120% AMI still qualifies for some units.
