I think there exists a certain irony in that the person responsible for the most bans in the history of the forum and managing to squeeze that into a single day talks about being against ostrazisation on loose grounds.
I think comparing exclusion from online communities to physical abuse or the justice system is inherently misguided. Being part of an online community is not a right, it's a privilege and the primary goal of anyone managing a community is to do what is best for that community.
Waiting beyond all reasonable doubt to verify that someone is a bad actor often leads to that bad actor having plenty of time to poison your community, just like a gardener can't afford to wait until the blooms wilt to do something about the weeds, so does a the manager of a community have to be pro-active. They need to encourage the behaviors they want to see and they need to root out what looks to be a weed even at the risk of it sometimes not being one.
This is no great injustice, there's countless of other online spaces out there for anyone to join or even create their own ones.