>IMO, flying cars will eventually arrive.

Not so sure. I saw specific designs hyped in the 80s and 90s, and know of efforts hyped in the 70s as well. The reason they always fail is because constraints of designing a car to go on land and the constraints of designing a flying machine are different. You can sorta kinda build something that does both, and people have, time and again, but it will be good at neither of those things. Well, unless we develop "antigravity" or something...

Add the possibility of huge damage caused from a failing/failing/crashing flying car, not just to the road and other cars there (like with a car) but to any building, group of people, etc. If it was a car-replacement (and thus getting on it was laxer than flying a plane, with flight plans, airport checks, special licenses), it would also be perfect for suicide terrorism too!

Here's a funny but insightful post I've found, hammering on the topic:

Listen to most discussions of flying cars on the privileged end of the geekoisie and you can count on hearing a very familiar sort of rhetoric endlessly rehashed. Flying cars first appeared in science fiction—everyone agrees with that—and now that we have really advanced technology, we ought to be able to make flying cars. QED! The thing that’s left out of most of these bursts of gizmocentric cheerleading is that we’ve had flying cars for more than a century now, we know exactly how well they work, and—ahem—that’s the reason nobody drives flying cars.

Let’s glance back at a little history, always the best response to this kind of futuristic cluelessness. The first actual flying car anyone seems to have built was the Curtiss Autoplane, which was designed and built by aviation pioneer Glen Curtiss and debuted at the Pan-American Aeronautical Exposition in 1917. It was cutting-edge technology for the time, with plastic windows and a cabin heater. It never went into production, since the resources it would have used got commandeered when the US entered the First World War a few months later, and by the time the war was over Curtiss apparently had second thoughts about his invention and put his considerable talents to other uses.

There were plenty of other inventors ready to step into the gap, though, and a steady stream of flying cars took to the roads and the skies in the years thereafter. The following are just a few of the examples. The Waterman Arrowbile on the left, invented by the delightfully named Waldo Waterman, took wing in 1937; it was a converted Studebaker car—a powerhouse back in the days when a 100-hp engine was a big deal. Five of them were built.

During the postwar technology boom in the US, Consolidated Vultee, one of the big aerospace firms of that time, built and tested the ConVairCar model 118 on the right in 1947, with an eye to the upper end of the consumer market; the inventor was Theodore Hall. There was only one experimental model built, and it flew precisely once.

The Aero-Car on the left had its first test flights in 1966. Designed by inventor Moulton Taylor, it was the most successful of the flying cars, and is apparently the only one of the older models that still exists in flyable condition. It was designed so that the wings and tail could be detached by one not particularly muscular person, and turned into a trailer that could be hauled behind the body for on-road use. Six were built.

Most recently, the Terrafugia on the right managed a test flight all of eight minutes long in 2009; the firm is still trying to make their creation meet FAA regulations, but the latest press releases insist stoutly that deliveries will begin in two years. If you’re interested, you can order one now for a mere US$196,000.00, cash up front, for delivery at some as yet undetermined point in the future.Any automotive engineer can tell you that there are certain things that make for good car design. Any aeronautical engineer can tell you that there are certain things that make for good aircraft design. It so happens that by and large, as a result of those pesky little annoyances called the laws of physics, the things that make a good car make a bad plane, and vice versa. To cite only one of many examples, a car engine needs torque to handle hills and provide traction at slow speeds, an airplane engine needs high speed to maximize propeller efficiency, and torque and speed are opposites: you can design your engine to have a lot of one and a little of the other or vice versa, or you can end up in the middle with inadequate torque for your wheels and inadequate speed for your propeller. There are dozens of such tradeoffs, and a flying car inevitably ends up stuck in the unsatisfactory middle.

Thus what you get with a flying car is a lousy car that’s also a lousy airplane, for a price so high that you could use the same money to buy a good car, a good airplane, and a really nice sailboat or two into the bargain. That’s why we don’t have flying cars. It’s not that nobody’s built one; it’s that people have been building them for more than a century and learning, or rather not learning, the obvious lesson taught by them. What’s more, as the meme above hints, the problems with flying cars won’t be fixed by one more round of technological advancement, or a hundred more rounds, because those problems are hardwired into the physical realities with which flying cars have to contend. One of the great unlearned lessons of our time is that a bad idea doesn’t become a good idea just because someone comes up with some new bit of technology to enable it.

When people insist that we’ll have flying cars sometime very soon, in other words, they’re more than a century behind the times. We’ve had flying cars since 1917. The reason that everybody isn’t zooming around on flying cars today isn’t that they don’t exist. The reason that everybody isn’t zooming around on flying cars today is that flying cars are a really dumb idea, for the same reason that it’s a really dumb idea to try to run a marathon and have hot sex at the same time.

https://www.ecosophia.net/progress-and-amnesia/