OK, a planeload of 200 international passengers lands at JFK.
40% of them, 80 people, want to go to the same hotel in Manhattan via Lillium "taxis". At 5 pax per load, that is 16 Lilliums. (Lillia?) But there are only pairs of passengers, no single travellers, and they all have a pile of bags.
There doesn't seem to be a cargo compartment, so the bags go in the back seat. That is now 40 Lillia needed.
The landing pads shown in the videos generally depict one central landing spot and 4 parking spots. Say we start with 4 Lillia already on the spot, charged up. 8 pax load their own bags, and hop in. One by one, they stagger into the air and by the magic of their computerised flight plans, they avoid conflicting with the real airplanes landing every 30 seconds at JFK on the alternate runways. They will NOT be blasting off in a straight line to downtown like shown in the videos.
The other 72 people are waiting for another Lillium. They have to come from somewhere, so it takes time - they can't be buzzing around airborne waiting for a landing spot, as that will chew up its battery life, and besides there isn't enough available airspace for 4 more or 36 more to be orbiting the rooftop of the Acme Airlines building. Passengers waiting. Waiting. Stuff it, a real taxi will be faster.
See a problem? The fluffy thinking doesn't allow for any practicalities.
A 300-km range is from fully charged to dead empty. You gotta land with some reserve power, in case some other Lillium is already on your desired spot, and if it flew into JFK to pick you up, it already has a decreased range. Then when you hop out, it doesn't have enough power to go back to its home base, 280km away, so it has to occupy the pad until it is charged up - if there is a facility to charge it.
But this whole industry will keep the CGI people in clover, drawing up more and more Jetson-like creations and asking gullible people to invest in it.
They talk of redundancy - showing that if up to 4 engines on one side stop, the rest can take over. What if they are all at max power already in the hover? A rapid roll takes place, or else it shuts down 4 on the other side, and a descent takes place.
Using too many brain cells on this one, I will have a beer instead and kill them off.