As someone who only frequent one of the tamer niche interest board where there are seldom trolls posting slur/gore/porn, my view may be biased, but I would argue that the anonymity that allowed hate speech also enables people to be more candid in their posts and therefore leading to a sense of community.

As long as I don't put anything personally identifiable in each post, the chances of them being linked together to point back to my real identity is miniscule, so I can share stuff I would normally want to keep private.

I have bonded over deeply personal trauma with anons that I will never knowingly meet again but also know they are out there on the same board as me. I've commiserated over health concerns that I wouldn't share on social media in fear of seeming unprofessional nor with friends to avoid making them worry.

Hell, I made a throwaway just to post this since I don't want people to look at my profile and go "that guy is a 4chan user" since that could be an issue professionally, yet nothing I said here is a hate speech. That's an example of how anonymity allows for more honest speech in ways most sites elsewhere don't offer.