Did you read the document linked in Jennifer's original post?
Oops! I didn’t! I’m sorry Jennifer!
It contains some examples of the numbers you are talking about. Specifically:
80% of sessions with a poorly performing GPU are represented by relatively common GPUs
Sessions under 10 FPS are reduced by 55% by blacklisting
Sessions under 20 FPS reduced by 33% by blacklisting
We made a conscious decision not to share data about specific low-performing GPUs, but perhaps we can make some of that information available through private channels if you believe that it will help better make the case within Apple?
I’ll start with what you shared.