It's because the most massive costs an American has like healthcare, child care, and higher education are free or vastly less expensive in Europe. Americans spend all their time at work for a very impressive number on their paystub while they're still one accident or illness away from homelessness or bankruptcy. Europeans get higher quality of life/happiness scores and spend far less time slaving away for their boss. Just because the number on your paycheck is bigger, it doesn't mean you're winning.

> higher education are free

Many of the states[0] have started offering free or low cost tuition for their public community colleges and trade schools, and low cost tuition for their colleges and universities. For example, Minnesota offers tuition at a state college starting at $6k a year[0] and free tuition at community colleges if you're earning under $80k[1]. Those prices are before financial aid, grants, scholarships, etc which are widely available from multiple sources.

[0] https://www.sofi.com/learn/content/states-with-free-tuition/

[1] https://www.minnstate.edu/admissions/affordability.html

[2] https://www.nhcc.edu/free-college-tuition-nhcc

As for the rest of your comment, you have a very distorted of what life in the US is like. Also, nothing you list is "free" in Europe, there's just a lot of rather regressive taxes that are collected to pay for it all. The US federal tax structure is actually rather progressive, but that also means there's less money for the feds to pay for all of those "free" things.

Not sure we do have better quality of life in Europe. We may have in the 2000s, but we're in decline relative to the US. Even if you take things like healthcare into account:

US average disposable income is $67,000, while it's $32,000 in the UK (with higher rents in the UK than the US).