Marxists have empirically shown that when they gain power, they have a tendency to kill their enemies. This has been proven in in the Soviet Union, in China, and in Cambodia. As someone who is certainly not a friend of Marxism, I have a vested interest in ensuring that Marxists don’t succeed. And I’d be better off it they were shot, because they’d do exactly the same to me.
I’d be perfectly fine emigrating to an ethnostate. But since people tend to self-segregate, it isn’t very relevant who exactly moves; people of all kinds will gradually seek to be with those similar to them over time. It’s why gun nuts move to Texas and cyclists move to Seattle and Boston. The same principle holds true for race.