I prefer the assumption that people tend to be rational actors who account for their own costs than the assumption that there is some group of people able to rationally prescribe actions and account for the costs of other people they have never met.
What does meeting people have to do with anything?
It's pretty straightforward to figure out what the costs are of an UberX or Lyft driver, knowing their car model and year and also knowing how much they drive. These are facts, and they can be calculated once and held to public scrutiny and review. There's no need for everyone to redo that calculation.
Now that we have something that can be calculated, we can move forward based on reason, without having to decide which of two assumptions we prefer.
I suspect Uber and Lyft would continue to experience their current glut of drivers, even if the entire model boiled down to nothing more than drivers effectively trading the equity of their vehicles for cash at a terrible exchange rate.