Cars have basically unlimited useful life because every component (arguably with the exception of the frame) can be repaired. It's surprisingly affordable to rebuild an engine and make it as good as new. I can buy a car made in the 50s today, that's a 70 year old car. And I can keep servicing it and keep it going for another 70 years.

The main enemy of cars is rust, but for that there are cost effective mitigations now. The real reason people ditch cars is always they get tired of the old car and want something more modern, not because the car is at the end of its "useful life".

Batteries are not like that. They actually have a useful life that degrades over time, which makes them non-servicable.

What I would like to see is serviceable batteries, where you can replace individual damaged cells and keep the battery going. Everyone would benefit from that, especially the used EV market, which would help stem the massive depreciation hits EV buyers are facing now.