This is the problem. Medium is perhaps trying to drive people towards quality over quantity, but they have got it completely wrong in terms of rewards.
Quality and/or boosted writing never achieved anything in terms of growing readership and distribution - it was always back to square one with each new post.
What it did do was generate enough of a reward in dollar terms to make it worth putting a bit of extra effort and polish into a piece.
Once the $100 has dropped to $20 or less - no idea what the going rate is now as I've given up, and if i write a 'boostable' piece it will simply be as an experiment - there is no point.
No money, no momentum. No nuffink.