Many people comment under your message that Uber benefits from captured market shares and network effect. In this regard, the following article https://hbr.org/2019/01/why-some-platforms-thrive-and-others... (posted here a week ago https://news.ycombinator.com/item?id=20142912) can be of interest.

In summary, the article argues that some platforms, such as Uber, benefit far less than others (such as Amazon, AirBnB) from network effects due to the fact that their userbases are clustered over multiple locations :

> Drivers in Boston care mostly about the number of riders in Boston, and riders in Boston care mostly about drivers in Boston. Except for frequent travelers, no one in Boston cares much about the number of drivers and riders in, say, San Francisco. This makes it easy for another ride-sharing service to reach critical mass in a local market and take off through a differentiated offer such as a lower price.

The article raises others points and is quite an interesting read in itself. Strongly recommended.