those are not separate races those are slightly different cultures at most

Racism isn't based on biologically real 'races' (not least because there aren't any). There's no Irish 'race', but "dis tick Paddy" jokes are still racist.

can't you at least accept that I am NOT against any ethnic group

That's exactly what I can't accept - because if it were true you wouldn't have the views that you do. If my neighbour told me they wished I'd never moved to their street, I'd conclude that they disliked me - even if they tried to tell me otherwise. If someone says they try to avoid working with Jews, I conclude that they're prejudiced against Jews - even if they say they're not. And if someone says they wish non-English people hadn't come to England, I conclude that they're prejudiced against people with a non-English background *in* England.