Flying cars would need to be regulated like airplanes and have lots of automated safety features.

Personally, I do not see this ever happening, unless they are entirely 'self' operated, or are all part of a vast fleet operation that directs every vehicle on it's course - No human input. Otherwise these things would be flying into everything, bouncing relentlessly across the surface, rivers and lakes would be filled with errant vehicles,... It would be the worst single move in people moving in the private sector. Look at all the idiots who drive in the most mind boggling ways now - Distracted by hand held devices, doing make up, eating, barely watching the road, reckless drivers,.... Now look at the idiots who ABUSE the 'self drive' modes in Teslas already. So without a integral hub that monitors and operates every vehicle in the air? No.

Adding a third dimension (height) to traffic patterns would multiply road space, leading to far fewer accidents. But yeah, the idea of flying cars is horribly implausible.