1. Free speech as some sort of abstract enlightenment ideal.
2. Cases of clear injustice in our past that stemmed from denial of free speech.
But that's not really why this article was posted, was it? It's really part of the ongoing modern conversations we're having around certain groups claiming their free speech rights are being infringed.
I think that injustice was done to Galileo, but I'm not going to shed a tear for somebody who was booted from an internet community for arguing that certain races have a lower IQ and LGBT+ folk are degenerates that need to be sterilized, even if they do it in a faux-earnest way.