Previously forums were mostly highly categorized and discussions had to be kept on topic as going off topic was considered incredibly bad etiquette. With yahoo answers there was only a few days for answers to post before the question asked had to judge best answer. Irrelevant and off topic responses were deleted as spam.
Since Reddit, and the way Reddit is, posts end up being buried after a few hours and if a discussion manages to start you can guarantee it will be diverted in the responses. This isn’t even restricted just to conversation on important conspiracies, such as what we need to do about the Jews (which would quickly get deleted anyway). Even some random kid asking for homework help on the Norman conquest of England will end up getting comments diverting the discussion to Putin and trans.
This has meant that it encourages people to learn to engage in disjointed and divergent thinking- previously a sign of mental disability.
anti trump and political censorship isnt even the main problem.
I said it above, ive been banned from totally non-political subreddits because most questions you would ask, and most comments you would make in any given subreddit are against the rules. not just offensive ones.
the rules on each subreddit are basically primed to support certain individuals and prevent people from asking certain questions or discussing certain topics.
its to the extent someone could be mentally distraught and suffering severe mental illness scared or bothered by a specific topic going on in their life, but discussion of the topic is banned.
or you could just inadvertently say you did something related to a subreddit topic i.e. "I pierced my own ears" -- self piercing discussion is banned thus you are banned. too bad you didnt memorize a laundry list of rules preventing any discussion of anything important or any REAL questions a person might have.
the only things you can post on there with questions are obvious questions one could simply go see a doctor or ask their piercing artist in person about.
the censorship goes beyond political. sometimes it supports specific businesses and undermines competition, other times it protects social-hierarchy access to information (by only allowing questions from people who already have the answers), and yet other times it just staunches discussion.