Extremism is never the right thing to do. You can't eliminate all bots, you can simply make them non-profitable. Maybe this will happen with communities - who knows. But as of right now - steem is a decentralized system where everyone has the freedom to do what he wants and if he/she wants to use 100$ to get on the trending page - then this is her own right.
Even if there wouldn't be any bots anymore - vote-selling would still not be solved. But you are right - we have to change steem for the better!