That's the trend I've noticed. Lots of 20 and 30 year old live in SF. Once the family expands, the first question is "when do we move out of the city?".

When you've got kids, things like bars and restaurants take a back seat to good schools and family-friendly neighborhoods.

Of all my coworkers with children, maybe 10% chose to stick it out in SF and they seem to bitch non-stop about the schools.

It's not predetermined that neighborhoods in the city aren't "family friendly" though, that's a choice we've made though policy.

Well, part of the family-unfriendliness is competition for cities' limited housing supply.

If a family with two adults and three children wants a 3-bedroom property, their budget depends on two adults' salaries minus the costs of three children.

On the other hand, if it's house-shared by four childless adults in their mid 20s, their budget is four adults' salaries, with none of the costs of children.

Lots of cities manage to do well with children; New York is an above-average performing urban school district with a million kids enrolled.

The problem is that with the rise of housing as an investment vehicle, cities have rapidly increased in price. In most countries housing is not a high-yield investment like stocks, it's a safer, low-yield investment like bonds. REITs have managed to destroy the goal of affordable housing for most people.

I wouldn't blame it on REITs but the vastly greater real lifetime income of the previous generations. Wages have been declining since the 70s.

I can't speak for OP, but most of my co-workers are in their 40s and 50s, but they live in SF or very built up inner-suburban areas. Not saying this is true of everyone, but this common trope does have some contradictory anecdotes.

> What is your coworkers' age range.

20s through 50s.