I think the "too powerful" is a convenient half-truth that also helps with marketing, and more importantly keeps the model from being distilled in the short term. They'll release it "to the masses" after KYC or after they already have the next gen for "trusted partners".
I feel bad for Anthropic because they thought Persona was an acceptable KYC provider. It probably was a genuine mistake. I might have to leave them over that, if they think it's fun to ask me to give Peter Thiel my ID to persist indefinitely on Persona's servers!!!