//what untitled is saying is that caucasian is not a protected minority..//
I don't know if that is what he's saying but whether that's so or not, it is incorrect. No individual racial groups are "protected minorities". The law says that discrimination on the basis of race is illegal. So it doesn't matter if the victims of that discrimination are white or black. But this intrigues me:
"..come back if there's a campaign to systematically and permanently remove white people from theatres and i will agree it's racist... until then... nah//
So one occasion of discrimination on the basis of race is OK (provided the victims of that discrimination are "only" white). What about two? Or twenty? Where is the line drawn between such a practice being acceptable or not?
This proposal is racist, plainly and simply. To excuse it on the basis that it is OK to exclude white people because "...in the UK black people are a minority who have been long mistreated" is simply indulgent tosh.