First of all, it seems like the plagiarism checker isn't doing a great job at removing a good portion of the $$$AI$$$ cheaters. It is alright, but it isn't great. And as $$$AI$$$ tools get better (and cheaper), the amount of cheaters in the top $$$1000$$$, $$$500$$$ and $$$100$$$ spots in $$$div$$$ $$$1+2$$$ s will increase.

In my opinion, I don't see any way to reliably automate the removal of $$$AI$$$ cheaters. You pretty much need actual people to look at potential cheaters and determine if they are actually cheating.

Of course, the codeforces admins don't have the time or resources to do all of this by themselves (that is, look at all of the potential cheaters and then ban the ones that they determine are actually cheating). But the cf community actually can do this, and I think that some members would enjoy doing this. There is already a pretty good cheater database out there, and a lot of the cheaters in it have not been officially caught by cf, so the community is definitely capable of identifying cheaters that codeforces itself isn't identifying.

So I think that codeforces should give the community limited permission to ban users. This would have to be done in a careful way, though, like maybe there are $$$4-6$$$ trusted community members that can vote on banning a certain user, and if the vote to ban them is unanimous, the user gets banned. The admins wouldn't even have to do anything.

It doesn't have to be done that way, though, like another way to do it would be to just ban everyone in the current cheater database. If the database is carefully maintained, this would also not be a bad option, in my opinion.

My point is that if we continue to leave most (all?) of the banning up to the admins, a good deal of cheaters simply won't get caught. And since codeforces has an active community that cares a lot about identifying and banning cheaters, not using the community to directly assist in banning cheaters is a waste. That is all.