Oof. I know people with kids in the city, and it seems like if you're taking public transit, it's a nightmare when they're little.
(When they're teenagers who knows, you have new problems)
People who live outside of Manhattan have more space and sometimes the optional car.
The professionals are paying an absolute fortune for child care, a salary's worth, and more for bigger apartments in nice neighborhoods.
It's no joke. You'd better be obsessed with the city, or a short commute, because otherwise you're moving to Westchester or NJ or LI.
My little kids looove transit. We take the bus all the time in my small town. We visit San Francisco almost weekly it's how we get around after parking. And we usually start our day in SOMA, an area that is not the nicest. We also frequently take the new central subway. I have not experienced a nightmare yet. Maybe Manhattan is more of a nightmare.
I have no doubt that Manhattan is expensive, but my greater point is that it would be great. A lot of very expensive things are great.