Of course, it wouldn't be a 22% decrease, it might be an 11% decrease if we assume optimistically that operating costs are cut in half. I don't know if administrative efficiency is exactly a strength of the government, either.

The main cost benefits are that you don't have to pay for marketing, underwriting, plan administration for a bunch of different plan types, negotiating with thousands of employers on the premium they'll pay, etc.

I think an 11% decrease is conservative if anything. None of our peer nations spend more than ~5% on administration as a share of overall healthcare spending.