When I click that link, and go there in a browser without logging in, I only see 70ish comments listed. But I also see a lot of removed comments as I scroll down, mostly from a single user. My uneducated guess is that there was already some chicanery in the thread, which the Mods have dealt with, and you are seeing the result of that.

As far as what can be done about it, there really is little to be done, as log as Lemmy remains open (and federated). Posts and comments hop around from one instance to the other, and while some instances can take a hard line against bots some other instance can be more permissive then it becomes a game of whack-a-mole. Active, open moderation is the best cure, but takes effort.