This is a SICK JOKE being employed by the "haves" here against the "have nots." You can not spin it any other way. Consider your own words:

"The rewards curve is changing. We expect posts that would make more than 20 STEEM under the old rules to earn more after the changes. Those posts that would have made less than 20 STEEM under the old rules will receive less after the changes."

How does THAT encourage the vast majority of users to try harder to provide good content? This is a bald-faced additional way for Steemit to keep empowering the already powerful here at the expensive of those in the 99% of the pyramid below those fortunate 1% who already don't need any more rewards.

And, this is just as bad:

"A downvote mana pool is being added, which will allow you to make a few downvotes each day without impacting your ability to earn curation rewards from upvotes."

The most pernicious of Steemit's traits is thus being EXTENDED and made easier for those who engage in malicious downvoting without even, now, paying any penalty for their ANTI-DEMOCRATIC CENSORSHIP of those whose world views (or hair style, or age, or gender, or whatever...) they don't like.

Steemit once had a chance to be a truly egalitarian tool for good in this world. This Hardfork pisses on that idea, destroys any hope for the future of success of the platform, and proves that the top 1% here are as corrupt and greedy as the top 1% in the general population.