I cant speak for everywhere in Europe but, here in the UK, that's just flat out wrong. We have a history of making legal progress in regards to discrimination faster than the US which has allowed the population to adjust to a much more equal way of living.

Slavery was abolished 58 years earlier, voting laws are hard to track given suppression but the UK passed legislation to combat suppression 37 years earlier, homosexuality was legalised 36 years earlier, there were never any laws against interracial marriage here, there were never any segregated schools here, 'ethnic groups' wasn't even a category of statistics here until 1991.

I can offer you both a modern and historical example of Americans being unadjusted to the level of equality in the UK. First, in WW2, there was often violence between British and American soldiers over the treatment of Black soldiers when Americans would discriminate. This is even evident from US instructional films of the time. Today, while BLM affected the UK, there was general consensus among even left leaning MPs that the movement was outdated for UK social reform. There's plenty of debate footage to attest to that.

The main sources of discrimination in the UK today stem from xenophobia, which whilst a large problem, is nowhere close to the shitstorm on your end.