An adult making 150k with a partner who makes a similar amount is not rich in a city like NYC. I broke down the math above, but in no universe does the typical upper middle class family have an extra 86k per year to spend on school
Just tell your kids you aren't going to pay for Vanderbilt and they'd have to go somewhere cheaper if you are footing the bill. Plenty of options. My parents told me if I wanted to go to college I was completely on my own.
Right now tons of people who's parents just refuse to provide financial information don't get any aid at all. This is very common if you have a bad home life. I fell into this category.
I grew up on welfare and I'm at the level were if it worked out with either of my last 3 partners we'd be at 300k or more. Life is funny...
But what's your definition of "reasonable"?
Income is not a bell curve, but one standard deviation on a bell curve goes up to the 84th percentile, and two standard deviations go up to almost the 98th.
It's not a reasonable income to expect, but it's a reasonable income to have.