So... Europe is a big place, but I would be fascinated to learn on what sample you are basing this assessment of European schools.
Not that I disagree with most of your other points.
Personal experience in education systems in 2 western European nations (two different languages, one being English).
A close family member who's a teacher in the second nation (and my husband was educated in it along with the rest of his family). We've had numerous long talks about the education system there.
A child who completed elementary school in a school run by a third nation (a third language).
Close friend and university faculty member who wrote exam questions for the UK A levels and shared questions with me (we would converse about them). I have not experienced the UK education system personally.
I don't know about Eastern Europe. I have friends from there and they all seem to be well-educated, but they're also a skewed sample of university-educated people.
That said, a friend from one of the nations I lived in also moved to the US. He said once, "I have better, more intellectual conversations back home with random people who left school at 15 than I do here with supposedly college-educated people." Everyone in the group agreed. It's a sad comment on our education system. Recall the studies showing that US college students don't learn much.
This one from 2011 A discussion here from 2018 Graduate schools here can be very, very good. But there are also a lot of non-Americans who fill the slots as postdocs and PhD students, especially in the STEM fields. There are multiple reasons for this, but one of them is that our K-12 education system doesn't do its job properly and too many bright people drop out of rigorous undergrad programs.
I'm not trying to claim that schools in Europe are perfect or even incredibly universally wonderful. I know they have problems. But are they better than US schools on the whole? Absolutely. A huge part of the difference is that those societies see education as something that benefits the society and invest accordingly, whereas Americans see it as something that benefits individuals and invest accordingly.
