If you carefully read my message and all the conditions you’ll see that 400 will melt faster than you think. Also it will be closer to 200-300 because you spent part of the sum to buy a house.
I could raise a kid in my apartment, plenty of room. My parents raised 4 kids on less than i make, even adjusted for inflation. My friends with kids are not making 400k/yr and doing just fine.
This is why my remarks about "where you live" and "ambition"