Because the people promoting alternative forks were using scripts and bots to censor the original bitcoin developers, criticism on the forks, and other discussion not promotion...
There is a long, long tradition, going back as far as the end of 2013 of censorship of any criticism or even any bad news about bitcoin in /r/bitcoin
Funny thing though is that /r/buttcoin that was made as a criticism of bitcoin in general is actually much more open and censor free than /r/bitcoin to the point that you can actually read some technical pro bitcoin articles there without any censoring or even down voting.
Funny thing though is that /r/buttcoin that was made as a criticism of bitcoin in general is actually much more open and censor free than /r/bitcoin to the point that you can actually read some technical pro bitcoin articles there without any censoring or even down voting.