I recently spoke with an elderly woman in San Francisco on exactly this subject. She regarded Uber as the best thing that's happened to her life in the past decade. It enables her mobility in ways that taxis never did.
This is hard to argue. For one since American perspective is different from my German/Europe and that's an individual, not a larger perspective on society.
The key difference, I think, is that in your background taxis are an affordable and reliable source of transportation services for all. They provide peak and off-peak services, for routes lucrative and otherwise.
The American experience I have had with taxis is that taxis are expensive, unreliable, and will try to ditch you if they deem your destination insufficiently lucrative. When you need them most, there's a very good chance that they won't show in a reasonable timeframe... or show at all. Which is to say that they avoid providing as many of the society-level benefits you describe as possible.
San Francisco in particular was a hell of useless taxis. For a long time, calling dispatch to get a taxi left you with odds of under 50% of one actually showing up.
From my visits to the U.S. I understand some if the disfunctionalities of U.S. taxi systems, similar to most other U.S. infrastructure, while not having deeper insights. This ruling is by an European court about European markets, though.
