I don’t think that introducing electric motors into the mix is going to be the factor that drastically changes the above ratios.
Very confident you're wrong in that sentiment.
American urban design is awful. It's really bad. And I would feel safe claiming that most Americans who might consider bikeped commutes rule it out because it is just not practical with our sprawling, idiotic suburban model.
That electric motor decreases your delta with prevailing traffic substantially and massively expands your range both as a function of literal distance and as a function of how far you can get in a given time. ebikes have absolutely HUGE potential to act as a transition as US urban planners (hopefully) get their act together and stop building financially and environmentally unsustainable, ugly, unsafe cities -- and start opening the door to the kind of infill needed to fix the already-busted ones.