> would the 45 minutes of reserve fuel really be necessary if you're not constrained to use an airfield?

Yup. High winds in an area would make it unsafe to land anywhere in that area. Ditto for low cloud cover (need a minimum of 1000') or low visibility (need more than 2 miles).

From an overview of the differences in regulations that cover Helicopters (which are likely more maneuverable at low speeds than this aircraft):

>>> Helicopters must complete the flight to the first airport of intended landing, then fly from that airport to the alternate airport; and then fly after that for 30 minutes at normal cruising speed. Normally, other aircraft are required to have 45 minutes. <<<

http://www.cfidarren.com/hpart91.htm

Long story short, batteries are heavy, heavy beasts. Generally available electric vehicles have trouble going much over 300 miles on a single charge; aircraft are going to have even more problems.

As a taxi service, the unit would have to travel to the client, do the client's run (repeat those two steps if possible), then return to base where the batteries can be swapped out, all while maintaining some degree of emergency reserve. I'm not sure how useful it would be for a taxi service if it only had an hour or two's endurance.

If the batteries can't be easily swapped out, then there's quite a bit of downtime in charging as well.

5-10 minute charge time is just as good as swap out without the overhead. It's difficult with current tech, but is indeed possible.

> I see this moving really slowly unless the company is commanded by an exceedingly talented team that understands how to influence governments to update policies.

Isn't that what Uber's talent really was? Getting policy challenged and the hundreds of local and state lobbying efforts?

Fortunately the FAA is far less susceptible to such "talent". State and local governments have very little authority over aviation.