There was a thread yesterday about closing public libraries, and this sentiment ties into that; open and free access to information is important, because a lack thereof causes people to become blinkered and close-minded, which in turn makes them more susceptible for populist talking points (that is, a populist politician or propaganda telling you there is a Problem; when people don't have factual information to the contrary, or even a mindset of curiosity ("is that actually true?") they are more likely to accept it).

Hence, book burnings, censorship, and suppression of free speech are problematic.

(That said, I also believe that free speech should be curtailed on platforms with large audiences)