Proof of brain was a dumb slogan and never made much sense.

The idea is to allocate rewards to people who bring value to Steem, which is a collaborative process of stakeholders. (I'm not making up this goal now, it was literally stated in the original pre-launch white paper). 'Stakeholders' and not 'users', because it is stakeholders (or 'wealthy' as you somewhat snarkily call it) who are, at least under the current inflation-funded system, paying for all of the rewards, so it is stakeholders who get to decide where those rewards go.

Bid bots, vote buying/selling/treading, circle voting, self-voting all break this ability to collaboratively reward valuable contributions, which are supposed to feed back into making Steem grow and improve.

Now that we have made at least some basic game theory improvements that were obviously needed years ago, perhaps we'll see some improvement in the outcomes. It might not be the system or outcomes that everyone wants or expects, but it should, hopefully, at least be somewhat functionally better.