The left has never changed. Only the context in which they operate has changed. When they needed their voices heard, they pushed for free speech and expression to allow their emotional appeals to take root. Now that they have, and their side has general control of the status quo and the establishment institutions, and that the fruits of their labors are showing themselves to be culturally, socially, and economically poisonous, they need to silence people to resist a push-back, so now they are in favor of censorship, the thing they seemed (but ONLY seemed) to be against in the past.

The passage of time has revealed that deep down, most on the left have just as much authoritarian tendencies as anyone on the right, even as they try to smugly act like they don't; they view the government almost as a deific higher power. A trustable and nurturing entity that must be supported and expanded in order to, ultimately, redistribute wealth (as they see accordingly, of course). These people can not, and do not, truly care about expression or speech, only right-think and eliminating what they determine to be wrong think. In the past, that was by attacking religion. Now, it's by attacking logic and reason and facts and history.