The reddit #censorship problem is so chronic they actually have robots that detect whether an oppressed user reposts a #censored post in their own sub. #Reddit then suppresses that speech everywhere.
So e.g. you post something political in a sub with a "no politics" rule, it gets silently blocked, then you post in a sub where politics are welcome and #reddit silently removes the post even though it's rule-abiding.
*silent* non-tranparent censorship is maliciously insideous.