I did some analysis of the modlog and found this:

Ok, bigger instances ban more often. Not surprising, because they have more communities and more users and more trouble. But hang on, dbzer0 isn't a very big instance. What happens if we do a ratio of bans vs number of users?

Ok, so lemmy.ml, dbzer0 and pawb are issue an outsized amount of bans for the number of users they have... But surely the number of communities the instance hosts is going to mean they have to ban more? Bans are used to moderate communities, not just to shield their user-base from the outside. Let's look at the number of bans per community hosted:

Seems like dbzer0 really loves to ban. Even more than the marxists and the furries! What is it about dbzer0 that makes them such prolific banners?

Raw-ish numbers and calculations are in this spreadsheet if anyone wants to make their own charts.