I'm disappointed the article wasn't a bit more skeptical of some of the claims. Certainly the simulation-based testing is a good thing, but stats about how many billions of simulated miles have been driven can create a self-reinforcing delusion if everyone involved isn't careful to remember that the simulations can only work with well-known and expected situations. It sounds like Waymo realizes this and is building a…
I'm wondering why you say that? Wouldn't the more relevant factor be the type of miles, regardless of whether they are simulated or real? For example, 1 mile of simulated "Interesting Scenarios" (Duck on Street, Bicyclist going wrong way, pedestrian running onto road) is likely worth 100,000 miles of normal Freeway driving.