It’s not necessarily the case that pricing has to be the same across the board. The upper middle class complaint can be translated as tippy top privates ought to have the same pricing as (say) UCLA/Berkeley/UVA/UMich do for instate students. Yes there is state funding that helps to keep list prices down (and provides need based aid), but not that much any more and even if it was removed completely the sticker price would be a lot less than $70K per year.
But when it comes down to it many people also love to complain about the compromises that entails, like huge class sizes and difficulties getting the classes you want. You can’t have it both ways. And those who do attend the tippy top privates (whether rich or poor) don’t want their school to make those compromises either. But Berkeley and UCLA are doing a better job educating poor kids than tippy top privates, if you measure it in terms of % of Pell grant recipients etc.
Having said that, at our school most of the smartest kids from full pay but not ultra wealthy families are choosing Berkeley, UCLA, UCSD and UCSB over private options because the price/value equation works for them. We are fortunate to be in a state with great schools. It’s far worse for people who aren’t.