>The service contract states that all services are to be provided by them personally" - Yep. Uber drivers can't accept a route for someone else, or vise-versa "The services are performed on a continuing basis for the same payer.
That section you quoted applies if someone is in one of the four categories for a statutory employee. It's to decide whether to withhold Medicare and social security taxes from those already determined to be statutory employees.
The closes of the four categories is the first (beverage or food delivery driver), but it doesn't fit Uber.
Whether or not someone can subcontract is generally an important factor in employee contractor, but it's not necessarily determinative. In a variety of personal service cases you wouldn't want your contractor switching with someone else. However, you wouldn't mind if they hired others to handle the non-personal aspects of their business. Similarly, Uber doesn't care if drivers subcontract out cleaning and maintenance of their cars and other non-driving aspects.
Whereas they would care if "Steve" is in fact "John", because the service depends on reviews. That's similar to, say, Upwork, where if I hire "Steve" I want to know I'm talking to Steve. I don't care if he subcontracts, but at least part of the situation must be handled by him, because he's the one with reviews.
https://www.irs.gov/Businesses/Small-Businesses-&-Self-Emplo...
Meanwhile, you quoted a line from the financial services section, business control. But take a look at the factors actually listed in that section:
https://www.irs.gov/Businesses/Small-Businesses-&-Self-Emplo...
As far as I understand it, Uber drivers have significant investment (their car), they have unreimbursed expenses (car maintenance, food while driving, etc.), they can profit and lose money (if they are no good and their expenses exceed earnings), their services are available in the market (they can drive for others), and payment is per trip rather than an hourly salary (this last one is the most ambiguous, there are likely special considerations for the transport market).
I really don't think it's as clear cut as you're making it out to be.