Here's another cultural difference to add to the others.
If you believe it's a good thing for a country to have a generally positive attitude toward diversity, then you must acknowledge that the USA is morally superior to any European country. European elites overwhelmingly think diversity is a good thing, which makes the results of this survey problematic to them. How can a country which embodies so many things they disapprove of 'score' so well on a value they desperately wish their countrymen shared?
If you're neutral on that question, as I am, this is just an interesting difference. Doubtless the main factor here is that the US is a nation of immigrants, while European nations all have native traditions and populations and thick, deep cultures and identities.