> take a taxi driven by a human?

expensive, sometimes they sexually harass/assault the passengers, sometimes the drivers are also dangerously tired

> Or a bus (also driven by a human)?

slow (especially because USians oppose optimal stop spacing) and dirty, no door-to-door air conditioning, not separated from poor people

Tiredness is a big one. I was driven by a guy who had worked nonstop for a whole weekend. It was one of the most terrifying drives of my life. I had to tell him to park and sleep outside my house, or else I would report him to Uber.

> slow (especially because USians oppose optimal stop spacing) and dirty

It’s slow because it must solve for many possible routes. Cabs are point to point. A rideshared cab, moreover, knows ex ante where its customer is going and, in a city, where its next customer is.