The metric used here is an incorrect metric of social mobility. It compares father-son income correlation (which depends mostly on inheritance taxation and many other factors), while a better idea would be to compare the percentage of high achievers who started from humble beginnings.
Indeed, US education system is somewhat strange, to say the least. However, all these metrics are almost designed to present the US in bad light.
How about "the percentage of millionaires who were born in a poor family"? I bet this is where US shines. Rich people in most other countries are mostly from old money.
