yet they cost good-faith curators, sometimes considerably, it drives good-faith curators away from certain accounts, authors, topics, or away from manual curation altogether, as in your case

This is by design. Rewards are supposed to go according to stakeholder consensus. If there is disagreement, then rewards go somewhere else. In cases where the disagreement is consistent, it's a waste of your vote power to continue voting there, because it isn't going to be part of a consensus and get paid. You need to vote elsewhere if you don't want to lose out.

If people could just send rewards unilaterally, without regard to consensus or disagreement, it would just be tipping (which people can also do, without concern over downvotes).