A better service with better tech than taxis can make money. The market for the necessary backend services ends up looking like some hybrid of the market for web hosting and the market for geospatial data and services hosting:

Mostly open source software.

Competition is largely on price.

Plenty of small entrants into the market, fewer big providers, lots of resellers.

Many of the 'apps' are white-label skins on the necessary backend services, others are self-hosting the infra. Some local governments operate these services as utilities.

So, the software opportunity looks a lot like Automattic (the makers of Wordpress software and operators of the wordpress.com hosting service), which is a privately held company and valued at $3B.

I don't see what's the complex externality here- they can't raise prices significantly because they're legally prevented from doing so. 'The people with the guns & the legal monopoly on force forbid it' is pretty simple.

To my understanding the only people making non-poverty wages in the taxi business are owners who purchased 'medallions' decades ago- aka another governmental licensing restriction. I believe they frequently lease out the cars to drivers who make minimum wage or less. I'm not sure an individual taxi is necessarily profitable on a per-car basis