The rules have changed and people are still trying to live like their parents did.

Healthcare is expensive. If you are on Obamacare, it is subsidized.

Housing is expensive if you want to live in a "good" neighborhood. There are a lot of "okay" neighborhoods that people can afford just fine.

College is expensive, but it really depends on which university you go to. As much as anything, the college issue is intentional misdirection by the people who are steering parents and kids into those choices. There are very economical options, but the price tags and ramifications of those choices are usually not spelled out very well to the people making those decisions.

Edit: Childcare is absolutely expensive, to the point that I really expect having a parent stay at home to swing back around to being more normal. We have three kids and if my wife worked, it would cost more to have them in daycare than she would make while they were there.