It's not that any sort of moderation is an attack on free speech. It is that the meaning of the word "moderation" is being stretched and warped. When those sites began, moderation was removing illegal content (illegal in the US), and community moderation was ensuring on topic discussion. You could essentially say whatever you felt like, and those places didn't devolve into cesspools of hate.
Nowadays even on topic discussion and critical and informed discussion of controversial topics is "moderated". In some communities it is so bad that even by the letter on topic discussion that deviates from some community orthodoxy is removed. Worse still, in a lot of cases groups of moderators share lists of people to crusade against.
The problem I have is that the old, actual definition of moderation is used to show how productive communities can exist, and then that is given as an justification for this new form of suppressive moderation that does not produce productive discussion.
The distinction must be made between moderation and control of narratives. You might not want to call it censorship because it isn't a government doing it, but it isn't the same as what internet perusers have always referred to when we use the word " moderation".
