Since the 1970’s, Americans have become more tolerant of allowing people with controversial views to speak in public
The question of whether Americans have become more tolerant of speech is about recent changes, not changes since the 1970s.
There’s also the problem of how speech is classified. Those figures show that the tolerance for letting racists speak has gone down recently, which may be concerning—but it’s much more concerning if more things get moved into the “racist” category, which seems to be happening. Also, I don’t see “sexists” or any other category aside from “racists” that is hated by the left, and it’s quite possible that adding more such categories would show more downturns.
The question of whether Americans have become more tolerant of speech is about recent changes, not changes since the 1970s.
There’s also the problem of how speech is classified. Those figures show that the tolerance for letting racists speak has gone down recently, which may be concerning—but it’s much more concerning if more things get moved into the “racist” category, which seems to be happening. Also, I don’t see “sexists” or any other category aside from “racists” that is hated by the left, and it’s quite possible that adding more such categories would show more downturns.