Abuse can only be as big as the abuser's hive power. What percentage of hive power is owned by small abusers? Imo it doesn't matter to focus on this, just the big fish.

If abusers get too big, they are caught extremely quickly. I remember because I remember vote farming on steem when I didn't know it was considered a bad practice. 10k+ hive power accounts can't farm without being downvoted.