Well, if I were looking to test to see how one could manipulate, pressurise and 'de-person' someone for their political views, what I would do is start with those whose views people generally consider abhorrent.
Then everyone would be more likely to say 'well, they really are awful, maybe they should be cancelled/unpersonned/blacklisted'.
Then we could gradually start to widen the net of who is considered beyond the pale.
One effect of this might be to have people think 'well, they only unperson people who are really horrible, so that person must have been really horrible'. Thus we'll have a sort of preference falsification that is in effect 'no smoke without fire' and anyone who is accused of a thoughtcrime must be de facto a criminal.
Eventually, everyone will have to perform purity tests to participate in society, and this will be accepted.