I have a similar problem, but with a different user than you. About once a week or so, this user will go through my comment history and just downvote everything. I don't even know what his issue is, because he constantly deletes his own comments and has zero visible comments on his profile anymore, so I have no clue if I've somehow angered him or if he's just a random troll. Unfortunately, blocking him doesn't have any impact on this.
I agree, though. There should definitely be better protections in place against this sort of bad behavior. While I'm not a huge fan of Reddit's implementation of user blocking, it does at least prevent this sort of trolling from occurring. It would be great if there could be a middle-ground between what we currently have and what Reddit has.
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