That’s a myth white ethnics tell themselves to feel better. Blacks have been in the US since the 1500s and were being treated like this for countless generations up to and including relatively recent times. First generation Irish and Italian immigrants faced some discrimination, like immigrants today, but it was short-lived. We’re talking hundreds of years of identity stripping slavery and degradation for Blacks. It’s not comparable.
Over 50% of Blacks have come to the USA voluntarily. No one is stopping them from living in Africa. They choose to live in the USA because they consider it superior.
They - African Americans - consider White-majority societies to be superior. That's they choose to live there, since they think White-majority societies are superior to Black-majority societies.
No one forces Blacks to come to the USA, and no one would complain if they left - which is what they would do if they were truly "oppressed".
As for why Blacks get arrested more, it's because they commit vastly more violent crime. And Blacks get arrested more by police regardless of the race of the police officers, including in Detroit and Chicago, where most of the officers are Black