The autonomous vehicle industry is going through all kinds of turmoil at the moment. Lots of divestment and consolidation from major players including Uber, Google, Toyota and Apple. Why? Because they're realising it's much harder and we're much further away than first thought from achieving levels of safety acceptable to regulators. This is for cars which in many ways are simpler - apparently hazard identification is one of the major stumbling blocks, which may or may not be simpler for aircraft in controlled airspace. But the regulatory requirements will be way tougher so we're many, many years away from pilotless, and probably even single crew commercial flying.