Outside of regulation which requires companies to actually hold the reservations, and keep a certain number of reserve vehicles on standby it's not gonna happen

Outside of regulation which requires companies to actually hold the reservations, and keep a certain number of reserve vehicles on standby it's not gonna happen because customers will not pay the increased prices that such a company would need to charge. Effectively, the entire system is stuck in a local maximum that is much lower than the global maximum. One possibility is to simply charge an optional premium price to actually hold a reservation, but I suspect the premium would probably be too high for anyone to really take up and would simply lead to a lot of bad press.