I agree that every vote against a node which isn't based on that node's content is an abuse of the voting system. But does this really need a policy? In my opinion our simple voting system seems to be quite robust against abuse. Every monk can vote on every node just once, so there's an upper limit of "massive" downvoting, whereas nodes worth reading usually accumulate dozens of upvotes quite fast, even with the small community we have as of 2022. I wonder if I'd even notice if someone downvotes every node I ever wrote.
So I'd rather not grant the gods the permanent power to decide on users' XP. This will bring eventually up the question of Quis custodiet ipsos custodes? which I find problematic for a culture run entirely by volunteers.
I do appreciate the availability of the gods to receive complaints about a suspected malicious downvoting campaign, and whenever they find an abuse (any type of abuse) I'm ready to support their decisions to stop it. But trying to enumerate all possible ways of abuse in advance seems to be a waste of effort.