Some downsides bikes have which flying cars would not:

- No weather protection

- Don't work (well, if at all) in snow, ice, heavy rains.

- Limited (or zero) safety features, despite going fast enough to cause injuries and using the same infrastructure as cars

- Limited speed and range

- 2d congestion limits throughput

We have flying cars today, we call them helicopters, and there's millions of reasons why we don't have them in every house.

Equivocating a helicopter a flying car is akin to calling a Model T a Tesla with FSD.

And those "millions" of reasons all boil down to R&D costs. Reliability, inspections, takeoff-to-landing autopilots (they exist - have existed for over a decade - for military helicopter drones), etc. are all cost issues which are slowly being worked on.

The progress could be faster if it didn't rely on angel and startup-style investments and the associated NDAs and trade secrets, but I don't expect that to happen in today's political environment.

And they've been dumped all over city sidewalks in California because it's a legal grey-area.

Mine lives in my garage. Rental bike programs are... Hmm

Problems with those I-can't-believe-they're-not-illegal littering rental services, not the bikes themselves, right? Surely people aren't buying ebikes and leaving them all over the sidewalks.