The US has seen decreasing social mobility in past decades. So this isn't just the US vs European countries, it's the US vs itself.
https://www.weforum.org/agenda/2020/09/social-mobility-upwar...
https://www.weforum.org/agenda/2020/09/social-mobility-upwar...
The notion that people prefer to be “socially mobile” but poorer isn’t backed by a lot of evidence. People like more money, as a general rule.
Appealing to “social mobility” is something people with money do.
The people that don't realise this are nearly always the ones that grew up with a silver spoon and feel like they "worked hard" for what they have, when in reality most of their opportunities were open to them because of their social circle.