Are voices really protected? Could you cite the statute?

I really don't see the outrage. If I do an impression of Jordan Peterson am I also in violation of a social code?

You're intentionally missing the point. This is wrong and you know it. Impressions are different than building a model that can say anything using someone's voice, especially if they're recognizable and/or relative public figures.

It's like someone selling stolen credit cards and then claiming they're doing nothing wrong because people who are buying them are the ones committing the crimes.