If you think the problem with the 737 Max has been fixed, none of this is relevant. The crude estimate I gave is if you adopt the reasonable theory that the production/operation of the 737 Max is bad more generally, with the cause of the prior crashes being just one of the flaws discovered.

An illustrative example: suppose there was a plane model with 100 flaws that each cause a crash every 100B miles, and after each crash that particular flaw is fixed completely. The "correct" fatality rate would still be ~once per billion miles even after several crashes, and would only approach the standard airplane background rate asymptotically after dozens of crashes.