3.5M people work as truck drivers in the US, enough, in principle, to drive ~175M cars at the same time assuming 2% of cars need help at any given moment, ie ~60% of all the cars and trucks in the entire country being driven simultaneously.
Presumably though they'd be able to shave that down a few fold between where they are and dominating transportation nationwide (should they ever do so). So, it's pretty scalable in practical terms.
https://www.census.gov/library/stories/2019/06/america-keeps....
Can you clarify what you mean here?
For example - does the vehicle have to come to a full stop, as it can't safely proceed without an operator intervention? At busy periods, do they also have to wait for an operator to become available?
A busy junction could easily have 100 cars through it per minute. If two cars every minute stopped unexpectedly, that would hardly be scalable.
