Yeah, I think the used marked for ICE cars will be with us for a long time. There will always be people who need a car and don't have the savings to buy a new one, and if used ICE cars are cheap people will continue to buy them and drive them until they aren't worth fixing. So, there's probably a ten or twenty year lag between when ICE cars are no longer worth making and when ICE cars are no longer widely used.

(Some googling led to a claim that the average car life expectancy is about 8 years and 150,000 miles. That seems low to me, but maybe I'm biased by having owned long-lived reliable cars.)