Consider that many of these chips are in things like automobile ECUs, aircraft parts, industrial controllers, etc. Changing them requires pretty rigorous testi

Consider that many of these chips are in things like automobile ECUs, aircraft parts, industrial controllers, etc. Changing them requires pretty rigorous testing for timing issues, operating temp ranges, considerable design and test to meet regulatory requirements, etc. Different CPU probably also cascades to needed changes for parts around the CPU, software, and so on. Then, for any entity that successfully moves from one supplier with one process size to a different one...they are creating more demand there, which could precipitate shortages now in that space. Then, there's peripheral effects. Like perhaps some of the suppliers are liking the new per-unit margins during the shortage, and won't just let it all go when demand/supply normalizes.