Controlling what content is rendered on a site is speech itself. Government making rules infringes on my right what my software can and can’t display. It would be like the government telling Wikipedia can’t edit their articles.
Doesn't Wikipedia fall under the definition of a social media site with over 50M monthly users?
It does. This decision means other people “can’t censor” by reverting changes or overwriting.
No, it means that Wikipedia admins can't ban someone's account just because they disagree with that person's opinions. Wikipedia articles aren't supposed to contain (their user's) opinions anyway, so the admins should have no reason to base a moderation decision on such a criterion.