I'm writing from memory so apologies if there are minor errors, but there seems to be no consistent link between local immigration levels and hostility towards EU immigration. You're right about Boston and other agricultural towns (including Peterborough) in eastern England being strongly Leave...
Fair enough. There are four black members of my immediate family and I am pretty sure that they haven't experienced any significant racism. From what I can see, it isn't generally a serious or growing problem in our country, although I'll stick with my view that white blokes like me might not be...
To those of us with white faces living in the immigrant-friendly, small-L liberal southeast it doesn't seem necessary at all. Perhaps we're not the best judges though.