Uhm, they don't need computing at all, actually. And what they have for convenience, sensors and so on, we have countless low-density lithography facilities around. There's actually one for public use 50 km next to me, in a university. Someone on Hackaday lately even did their own low quality SDRAM in a self-built clean room. And even if not, you could just do a floating soldering job for most of it.

The high-performance chips are just for the bloated infotainment systems the ICEs have too.