Because the truth is, nobody, including WotC knows whether the middle ground or their current rate is better.
Well, note that they are already in a middle ground - they are between "the old rate" and "zero".
From there, it isn't actually about "knowing". It is about risk assessment and tolerance. And, well... you and I have very little skin in that game. It is really easy to suggest that they can put out more safely when your income isn't on the line over the choice.