Bitcointalk might not be censored now, as no contagious discussions are going on currently (some say no fruitful discussion on the BTC development is taking place here anymore), but it was definitely a thing back in the times of the big blocks debate, when mods were notorious for moving legit bitcoin-related topics to "Alcoins discussion" if they contained proposals they didn't like (i.e. proposing increasing the block size).

But, to be fair, Roger Ver and his crowd took themselves out of that debate by forking a new coin called Bitcoin Cash, effectively giving up their position toward the development of the actual Bitcoin, a move that always seemed strange (to say the least) to me.