I think judging any group of individuals as if they are all a single entity (be it through the lens of a particular majority view or a particular race) is discriminatory to the individual (hence discriminatory overall).
In your example (with made up numbers), if 20% are being denied citizenship and opportunity simply because they once resided in the same geographic region as another 80% (with different views), then that is discriminatory because they are not being viewed as individuals but are guilty by simply existing as part of a larger group that they have no choice over.
This is why we screen individual applicants, view each person as a single human with their own thoughts and needs, and judge everyone as an individual and not as a group; to avoid the wrong of discriminating against entire classes of people.
Far too many progressives support unlimited migration with no screening.
Conservatives and Libertarians seem more comfortable talking about treating everyone as an individual.
State policies do not operate in this fashion. See, for example, the reality of importing 1 million people.
The existence of a state pressuposes two "classes" of people: citizens and non-citizens.
Citizens are those who have lived and died, who have laboured and been taxed, and have made the very state which is constituted by them -- and they are owed, by that state, a society they wish to live in.
Non-citizens are everyone else. They are owed very little, at best, not to be killed elsewhere; but certaintly, not even to be aided. Unless you want to divide the wealth of every nation by 8bn and watch all of it disappear.
In any case, to non-citizens nothing is owed. Certainly not being carefully scruitnized under a microscope to see if a border agent can detect a lack of cultural or ethical fit.
And in any case, such a fit can be determined by citizens themsevles. And polled, overwhelming, citizens of western nations have spoken. And they have seen your dice rolling at the border, and havent appreciated its concequences.
THe presumption you have on the consent of your fellow citizens to give what you eblieve is owed to other citizens of other states -- this presumption is extraordinary, obniouxous, and short-lived. And much of your attitue here is shortening it.