Taxis are a complete piece of shit. In all my times taking rides to airports and to/from places - only taxis smell like complete shit, have ripped up seats, cars they never clean/vacuum, and also in general have asshole drivers who also try to exploit people (e.g. taking wrong routes, including tip, etc.).
Uber was the answer to that. Anyone can do it (because literally, just about anyoen can drive a car) so no more exploiting the market with shit like "medallions" and expensive certifications that are worthless.
So if you want to shit on someone/something - don't fucking look at Uber. They are the answer to the problem that was never fixed and was continuously exploited.
Now - to your point of contractors. As you said, contractors can set their own hours - which is definitely a given with uber. As far as rates - that is a laughable point. Just as much as contractors can state their rate, the company hiring their services can decline their rate. So no - it doesn't work like that.
Employees also have a set number of hours - and are given a specific guiddance (e.g., you will be here from 8:00 AM to 5:00 PM). Contractors don't have that restriction because it is simply based on performing the service.
There is zero question whatsoever that taxi drivers (or uber drivers, whatever you want to call them) are not employees. They have zero restrictions on where to work, when to work, etc.. Like I said, I ran into plenty of Uber drivers when I was going to Chicago weekly who would simply use it to help pay for their downtown parking every day. That is literally < 8 hours of "work" a week, and you think they are entitled to medical benefits and other employee-based shit like vacation? Yeah, sorry dude, that's laughable.