Like many other "tech" companies, Uber tries to show that they are innovative. However, they are not. Lets illustrate that with flying cars. The topic of flying objects which are heavier than air has been discussed lengthly in engineering. Therefore, it is relatively good understood. First, you need some force to counteract gravity (or disable gravity) and then you need additional forces to move around. In airplanes, this is done with wing which transform kinetic energy of the moving plane in lift. Therefore, either an engine is required to resupply the system with new kinetic energy or you require thermal lift. For vertical lifting, we developed rockets and helicopters which provide a counterforce + some extra to move an object up. All these technologies already exist. Yet they cannot be used to create a flying car which is cheap enough to make is an alternative to a car. Just compare the price and fuel consumption of a small helicopter and a car to see that this is not economical realizable for most people. Therefore, it is not an engineering problem, but a problem of theoretical physics to come up with a way to cancel out gravity. Unfortunately, Uber is not investing in that.
Second, average humans are not capable of flying devices. That is why pilots require a lot of training. Lets assume computer scientists and robot developers are able to create an autonomous flying machine, which is an enormous engineering task, as we are barely able to get it done with cars. Some might say, yes but we have autonomous flying drones and autopilot. The first fail often and military drones need supervision. Autopilots are able to steer a system through the air until something happens which requires human interaction. Also current flight is heavily regulated and controlled by pilots and controllers on the ground. In a "Fifth Element"-like scenario, thousands of cars are flying around. Therefore, you need additional rules, as they are closer together. Just like nowadays on the ground. An autonomous flying machine would have to mange all these rules and understand all other moving objects together which is much more complicated than 2D.
Therefore, such effort is futile, which let me conclude this is just a marketing scam used to show Uber is so great company. While the truth is, they are just a company with a lot of money form venture capitalists which provides an app and enterprise software behind it. Thus, they are just a business model not an engineering company and definitely not a company capable to come up with new physics.