The surprising thing is that parts availability is even worse for new cars. Sensors are built into every part now, so it's no longer just a windscreen or a bumper. If those sensors are critical to the driver assist systems, the car can be a write-off for trivial damage because of the difficulty of getting parts. And in many places, you can't just disable those systems and get on with things, even if the car is otherwise perfectly fine, because the law states that roadworthiness requires the original safety systems to be intact.

Even more alarmingly, the speed of revisions now is such that vehicles can have parts that were only used for a very short run before being updated and replaced. Your particular vehicle batch may not necessarily have identical parts to other batches even within the same generation. We're a long, long way from the way things used to be, when parts commonality stretched for decades.