Simply (and coarsely) speaking, the bot problem is due to "complicated (gamification of curation) unfair (superlinear reward calculation) incentive (curation reward)"
Removing the incentive can abate the bot problem, but I think removing the former two (complicated and unfair) also can reduce the problem significantly. See @sigmajin's post and @ats-david's post for further discussions.
I've said it in a few other places, but I support both ideas of eliminating curation rewards and switching to a more linear rewards calculation. Thanks for sharing @ats-david's post! I'll check it out.