The perception is that the left is in favor of censoring slurs and hate symbols. As a reaction, Trump/MAGA has brought back the R-word for instance.
Saying the Left are "pro-censorship" is not factually incorrect but definitely has a different connotation.
broadly speaking, it _is_ factually incorrect to say that. Censorship is the government controlling what information the public can access. No one on "the left" is trying to pass a law saying that people should get jail time for using the R-word.
Political correctness, woke/cancel culture, whatever you want to call it, is not censorship. And it's not splitting hairs to say this; words have meaning and though 'censorship' is particularly abused, it is still quite different from me looking down on someone who uses the R slur on X (as I do daily)