PG is implying that the phenomenon of getting shunned for having said something right-wing on Twitter is new/different enough that it implies some shift in societal attitudes. I'm arguing that it is not, and the 1985 equivalent would be a progressive being shunned for being, let's say, pro-gay-rights in small-town Missouri. The mechanism changes with technology, but the cause has not changed since Hester Prynne at least.