What does that have to do with present day? You're comparing two different times and circumstances
Well, we did have slavery. So I'm not sure I would necessarily call everyone since the Mayflower immigrants. Let's just say there has been a lot of movement of people into the US on a population adjusted basis since the Mayflower.
I personally don’t see much similarity between the mayflower (Europeans exiled to underpopulated territory in the empire) to a Chinese grad student coming to work a tech company. And that’s the ideal case!