I was always polite and respectful on Twitter and still wound up on a blocklist. So did many others. There was no notification or explanation provided and no recourse, I just suddenly found myself blocked from various accounts to the extent it degraded the utility of the platform.

Lots of people on the left love to be little commissars, and this sort of thing provides a perfect opportunity.

The implication of your statement is "you probably did something to deserve it, comrade" which is very much in keeping with that mentality.