Plenty of people buy used cars, especially young people and people at the low end of the wealth/income spectrum. My first vehicle was a 1990 Pontiac Grand Am that my dad bought for me when I was 18 for $900 in year 1999. I considered myself privileged that my dad could buy me a vehicle, even a $900 jalopy. Many young people's parents cannot afford to buy their child a car. Those kids who really want a car will buy a used vehicle with whatever money they can earn flipping burgers or stocking store shelves.
We can't just hand-wave away the fact that not everyone can afford a new car, or even qualify for a loan large enough to purchase one.
It's going to take manufacturers retiring their ICE vehicle assembly lines so that no new consumer ICE vehicles are available. ICE vehicles past their useful life that are on the roads now will need to be replaced with EV's. It's going to take a decade or more for this transition (Mine and my wife's current vehicles are nine years old and function perfectly well, and will continue to do so for several more years). While we wait for these vehicles to cycle out, we need a strong push to install EV infrastructure everywhere. I think it will eventually take a program similar to Obama's "cash for clunkers" that will incentivize stragglers holding on to their ICE vehicles to trade them in for a credit toward a new or used EV. Car dealers are not going to want those cars for trade-in because they are past their useful life.
And, for at least 4 years of the next decade, we should expect a Republican government who is going to put up every obstacle to the EV transition. I would not be shocked if the next republican president reverses any Biden policy to install or accelerate EV adoption.
Mystics always hope that science will some day overtake them. -- Booth Tarkington