I think the key issue is that when the OEM doesn't exist, software issues can likely never be fixed, and might make the car undrivable. For example, imagine th

I think the key issue is that when the OEM doesn't exist, software issues can likely never be fixed, and might make the car undrivable. For example, imagine the root filesystem of the infotainment system gets full with logs. Now it won't boot. But that system uses secure boot/disk encryption so you can't go in and fix it. And btw, the infotainment not working means the car can't be shifted into drive. No mechanic can fix that. The security features mean the parts can't be swapped from one car to another, and besides, even if you could do swaps, any swapped unit will get the same fault as the first. That is why the car valuation has dropped so much. The high chance that within a few years it becomes undrivable and unfixable.