If you read some of the linked articles off of the one posted a few comments back, then you will see that the recent cuts have disproportionately affected minorities, minorities are making less, and that minorities are receiving lower evaluation scores. So it seems they do have a diversity problem.
I want to see the actual studies that the guild has used to generate the numbers for their claims so I can see what possible mechanisms might be at play and what sort of level setting they've done for the data. Unfortunately, I didn't see any of the studies released.