I grew up thinking that jetpacs would be reality in the near future... All of these "vehicles" are just the 2010s version of the 1960s era jetpacs: super-cool and great TV fodder, and completely impractical
Physics dictate that a multirotor design will never be as efficient as a variable pitch propeller, and electric power is simply not enough to provide practical flight at a low-enough cost. Battery tech is improving, but way too slowly for these designs to be practical over the next 10-20 years. Unlike cars (where weight is a relatively manageable problem), flying machines can't afford weight. And if you believe in any of the claims for new battery tech, the devil is in the details (one thing is to have a battery in a lab, another to mass produce it). Elon Musk is pretty smart, and knows battery tech better than anyone: he's betting on the gigafactory, and the usual small incremental improvements we have seen for the last few decades. He would not spend that money if he knew of something better coming soon. Same applies to fuel cells and many other alternatives (and, unlike a helicopter, a multirotor needs electric motors, nothing else can respond as quickly with as much torque)
There's already a vehicle as small as a eHang MR that can take off and land in the same space: the Robinson R22 helicopter. It works well, flies for a long time, can carry enough weight to be practical. Can be bought used for ~$100k. How many R22 do you see flying every day as a commuter vehicle? There is no reason why a R22 can't be made to fly with an iPad (Arducopter can control a traditional heli like a multirotor). The problem is that certifying a fly-by-wire system for human flight takes a lot, and in many cases it's not worth it. Same would be for a multirotor. R22 are workhorses, used daily for cattle ranching in Australia, for example
Kudos to the people experimenting with those, but those will be as widespread in 20 years as the flying cars of 1960 are today. Flying is not energy efficient, and it's not a good option for short haul commute. Multirotors are great for hobby use and niche applications, not for full size vehicles. Aerodynamics is well understood, so there isn't much that can be done about the inherent efficiency problem of multirotors