You're still focusing on median which I think is a valid measure on its own but not wholly representative of mobility at all. I'm personally very biased, but I think social mobility is most important between upper-middle (usually the most educated and hard-working) and upper-classes because that's where the most value creation happens, and personally I think that it's much more motivating to have a chance to become very wealthy than it is to increase your income by $10k
> But once you remove sterotypes, what makes you think it's easier to climb to the top in America?
We have lower marginal income taxes, self-funded retirements, and proportionately less capital tied up in generational assets like buildings. My impression of the EU is that most of the upper class and upper-middle class are land/building/family business inheritors, whereas in the US equity in large businesses take a larger share of the upper/upper-middle class asssets.