What you are saying is right about Uber's current business. But that is not true for self-driving cars. The infrastructure costs of deploying a fleet of cars

What you are saying is right about Uber's current business. But that is not true for self-driving cars. The infrastructure costs of deploying a fleet of cars to compete with Uber if they gain market share will be massive, all but assuring they will hold a monopoly position for years unless a decentralized competitor could actually become reliable quickly (I doubt it).