What is the fatal flaw of the "open-source" taxi service?

Question

Computer networks

Taxi ordering services have been around for quite a few years, but there seems to be no "open-source" model anywhere in the world yet - there is an intermediary everywhere. From the point of view of the intermediary, it is understandable that this is beneficial, but why is it unprofitable from the point of view of the users themselves - a taxi driver and a passenger? And since this is still not the case, it can be assumed with a high degree of probability that it is really unprofitable.
What is an "open source" taxi service? These are all taxi drivers on the map in real time and one flow of orders from customers.
The obvious (for me) functions that fall on the shoulders of the intermediary company are a guarantee that a real order will reach the taxi driver and that the taxi will 100% come for the passenger (I can be wrong). But these tasks do not seem difficult to accomplish in the "technical sense" - they should be effectively solved by a transparent rating system, linking to car numbers and passenger phone numbers.

Answer 1

These are all taxi drivers on the map in real time and one flow of orders from customers.

the service solves the driver's problem - route optimization, the flow of customers the
service solves the passenger's problem - get an asap car, predictability of delivery time, protection of rights
And your "service" does not solve any of the above problems - in fact, both parties do not need it

Answer 2

From a technical point of view, there are no problems, the problem is in people. The guarantee would still be to reach the destination safe and sound, and open source services do not particularly provide this guarantee. That is why such services often work with intermediary services that have regular medical examinations of staff, etc.
Well, yes, not quite open source, but such services appear regularly. All sorts of services ala "podvezu.ru" or on a commercial basis. In Western countries, in principle, these are quite popular things, in France taxi drivers go on strike so much to close it all (they require a license from taxi drivers, but these dudes do not, etc.).

Answer 3

From a moral and ethical point of view, without regard to the law of a particular country, someone should check the technical condition of the car and conduct a medical examination of the driver before each exit from the garage. At the state level, this is implemented through car parks. Where and how fleets take orders to the state should be indifferent, the way it is and this is generally good, then the market self-regulates when the rules are equal for everyone.
A good rating will not drop much if the driver sometimes messes up a lot, and if there is, then such a rating will fall anyway from inadequate passengers.
Mobile application intermediaries often guarantee the driver payment for his services. This requires money.