Not having lived in Soviet Union, but having lived in a communist system, and am old enough to very much remember it, I think you have a very mistaken idea of repression of free speech in those systems post-Stalin.
So how did it work? It worked by intense social and governmental pressure, whereby expressing a thought that was "forbidden" led to incredibly overexaggerated offense and incredulity that someone could think WRONGLY like this (pro capitalist, anti worker, bourgeois, etc).
In fact, I have to say that over time, living here in Canada, I feel increasingly like that sort of totalitarianism lite is increasingly becoming familiar, where any even very minor dissent in thought is quickly shouted down as racist / transphobic / insert-X-phobic / anti immigrant, anti-whatever, even if said thought may bear no reasonable resemblance to supposed offence.
Not the OP, but a person born in the Czechoslovak Socialist Republic and with personal recollection of the late Soviet Bloc.
Obviously Reddit has no possibility to throw you in prison or execute you with a shot to the neck, but regarding the things that they can do against free expression of their users, they do not seem to show much restraint, especially if they can get away with it.
On this particular shitstorm, they will be faced to backpedal, yes. People hate pedophiles with passion.
