Sounds like the internet in general, to be fair.

The difference between 4chan and twitter in this scenario is that 4chan never made excuses for its behavior. Everyone on that site knew that you were on that site to be an asshole.
On twitter, all the hostility comes from people developing some real stupid takes for the purpose of showing that they're "one of the good guys."
Observing the development of 4chan and twitter over the years, people are, funnily enough, less of an ass when they're completely honest about being an ass.