Asking "what about left-wing subreddits" is whataboutism. Nobody is claiming bannable content shouldn't be banned because it's left-wing (except GP's implication).
crying 'whataboutism' is effectively ceding the argument I'm not sure why this term has been plaguing HN lately.
They learned a 'big word' and they use it to feel smart. It's like the time Peter Griffin learned the phrase 'shallow and pedantic'.