Yes, it would be reasonable to have separate per-user/user link limits. Though the limits could be a function of the number of comments that user made recently—if someone gets into a manic mode and posts dozens of trash comments in a few hours...
Right now, users with sufficiently high karma have access to the vote buttons on the userpages of users with sufficiently low upvote percentage, as far as I can tell to enable this sort of downvoting. It seems likely that exemptions could be baked it to these rate limits just as easily.
Yes, it would be reasonable to have separate per-user/user link limits. Though the limits could be a function of the number of comments that user made recently—if someone gets into a manic mode and posts dozens of trash comments in a few hours...
Right now, users with sufficiently high karma have access to the vote buttons on the userpages of users with sufficiently low upvote percentage, as far as I can tell to enable this sort of downvoting. It seems likely that exemptions could be baked it to these rate limits just as easily.