The elephant in the room is the battery technology is still no where close. The pundits who said three, four, five years ago the scientific discoveries would follow an exponential Moore’s law were hopelessly incorrect and vital energy density has plateaued. Furthermore the C rating, a measure of the recharge, discharge and life, means the best battery will struggle to achieve a life of more than a few hundred cycles and there simply isn’t enough Lithium to keep up with that kind of useage. Yes there’s been discoveries of cheaper low Li batteries but these are too heavy and haven’t a C rating suitable for this type of flying application. As said before, this problem could be solved in the next hour or in the next two hundred years, nobody knows. I fear investor inpatient will see this bubble bursting when promise dates are repeatedly missed and the crushing impracticality of these vehicles becomes inescapable.