I don't think Luxe style "wait for someone to razor scooter to you, then drive off" would work -- too far, and waiting even 5 minutes in the dropoff area of an airport would be obnoxious for the airport, and thus banned.

Actual valet parking at the airport would be great, though (with a manned facility where you drive up, drop off, and fly). I've been to airports which offered this. Aside from taxi mafia regulatory capture, I don't see why more places don't offer it. (On return, I'm indifferent between valet-returns-with-car, and taking a shuttle to your car elsewhere; the thing I want to optimize is dropoff speed.)

I think it's totally doable since you know exactly when passengers are coming and going (in fact, you'd see them right on your map).

You're "indifferent" between having your car waiting for you at the curb and taking a shuttle to off-site parking? Wow.

Car isn't "waiting for you" at a valet. It is "show up at valet, request car be delivered", which means waiting 5-20m, vs. taking a shuttle.

No airport has space in dropoff/pickup to hold cars for more than a minute, so they wouldn't be able to do valet pickup based on arrival time.

The service would monitor your exact location like Uber and pull up right as you're walking out the door.

At that speed I would wonder If I gave my car keys to the right person, or a scammer lying in wait.

Uniformed, and some kind of clearly marked kiosk officially sanctioned by the airport, with incentive to go after anyone trying to be a fake valet.

This has never been much of an issue in the valet or Luxe/Zirx business. I think it's very manageable even without some of the techniques available when both parties have a smart phone.