Yes, I know. But that has nothing to do with the question. If there are no players around, the pets won’t attack the monsters, either.
Interestingly enough, it seems that the final nail in the server’s coffin aren’t the AIs themselves, but the corpses. When there are multitudes of AIs, the server might groan and creak, and its FPS will go into “orange” with occasional dips into the “red”. But when the players let the corpses pile up, the server FPS gets firmly stuck in the red zone (1-3) and the ping goes from 500 (during the “good moments”) to 1020.
There’s someone – I don’t yet know who – on the official server where I play who does this often and on purpose. The next time it happens, I’m going in naked to snap some screenshots, to post them in a bug. And a freaking report, too, because everyone on the server is complaining when this happens.