I have a friend that works at one of these flying car startups doing battery physics. I can't remember which company, but the company has been doing R&D for 10+ years already and raised billions of dollars. IIRC their angle is more of a bus-type vehicle rather than a car one given the costs involved.

Based on the energy/power limitations alone, my friend wasn't optimistic about releasing a production vehicle anytime soon when I talked with him last year. Drones, which these are mostly huge versions of, seem to be advancing rapidly, but they aren't carrying humans so they don't need to carry much weight or be so safe they never crash or be capable of crashing gently.

The safety requirements mean more weight, more testing, and more time. Getting heavy stuff in the air means we need better and lighter batteries or other energy sources that we aren't using like microreactors.