Just last week (or so) Elon Musk stated he is not believing at all in flying cars due to lack of solid roads, ie it'll be a chaos with high risk of accidents when a lot of people will start flying.

Although technology can create virtual highways, Elon may indeed have a point, since these virtual highways require solid technology to create and for all flying vehicles to have the appropriate systems on board. This is already quit difficult to arrange for road vehicles let alone for flying vehicles where much more strict rules will start to be applied in all space what at this point in time is called "uncontrolled airspace". I mean: the uncontrolled airspace will soon become controlled airspace, declared by the existing air traffic control organisations as well as government, the moment some accidents start to happen.