It's a touchy subject, but important to note that the purpose of an incentive is to "incentivize" someone to take an action (i.e. buy an EV) that they wouldn't otherwise have done without it. It is not intended to be a "reward" for doing something you would have done anyway. Once EV adoption picks up and can stand on it's own, the incentives will (or should) end, otherwise is is a ripoff to the taxpayer.
I agree that eventually everyone will want and afford an EV and the incentives will expire but right now, that incentive is doing a lot to help me afford a Model 3 when it comes out. If it weren't for the incentive, I would have to think much longer and harder about swallowing the extra cost over just buying a much cheaper ICE. I would buy a Model 3 in a heartbeat if I can afford it but the incentive is what gives a ton of value to the car (not that it doesn't do well on its own).