>then I don't see how building automotive AI is core to a computer/mobile hardware computer company that has zero core competency in either car manufacturing or AI.

Autonomous Vehicle, is basically a Giant Mobile iPhone that you can sit in it. There will be lots of custom silicon doing software calculation, LiDAR making 10s to million of input every second, a gigantic battery, and lots of softwares.

Although I still think AV is at least another 5 - 10 years away in real world usage.