The US is unarguably less meritocratic than the amalgamated EU by every possible metric.... unless your conception of a 'meritocracy' is 'you have to be a genius to even stand a chance at doing better than your parents, otherwise, all that matters is how much wealth you were born into.'
...
Class mobility is worse in the US.
https://worldpopulationreview.com/country-rankings/social-mobility-by-country
Less people can actually manage to do better than their parents in the US than the EU (broadly, or aggregated and then adjusted per capita).
Income inequality is worse.
https://en.wikipedia.org/wiki/Gini_coefficient
The EU is thus less hierarchichal, stratified.
You are also not considering that the aggregated EU has better life expectancy, better levels of functional literacy and lower infant mortality than the US, ie, the 'shared environment' is at a higher baseline.
Not to mention the US's political systems have far, far more corruption by way of corporations and the wealthy being allowed to spend infinite money to lobby and advertise and propogandize for their preferred laws and policies.
Look up the Citizens United cass if you've never heard of if, or maybe observe the now regular, astounding and blatantly corrupt deals and grifts the current fascist regime does on a regular basis.
Or, if you prefer an academic source:
Thats over a decade old now, its only gotten worse.
...
The conclusions you are reaching fly in the face of obvious, exceptionally well documented facts.
You are wrong.