If 100% of new cars were EVs then there might be feedback loops that accelerate the long tail. Like gas stations becoming leas profitable, less prolific, and more expensive.

You might also see battery prices push the price of new cars well below that of second hand ICE vehicles.

Even if the replacement window for existing vehicles doesn’t change, the environmental impact would run ahead of the adoption curve. High volume use cases like delivery and Ubers would be the first to switch to EVs.