It's not a solution, but measuring and giving props to people who give out most of their upvote dollars to others is better than a shame list. That's good positive reinforcement.

Second, the problem is so much bigger than humans upvoting their comments. How much more money are the bots creators getting from selling votes, or people selling delegation power to minnows who will self upvote, or multiple account abuse, etc? Those are much bigger problems.

I don't know what the solution is....besides changing the underlying rules in the next hardfork.