There are only four fabs that can make modern CPU-level chips (Intel, Samsung, GloFo and TSMC), and their capacity was already maxed out. Then AMD started usning TSMC instead of GloFo, and even Samsung and Intel started offloading some of their fabrication to them, not to mention GPU makers due to the crypto demand. So now you have a single fab creating half of the chips in the world, already barely able to meet demand, and then the pandemic hit. So in that case, the chip shortage is understandable, this has been a long time coming. On the other hand, there are dozens of small fabs capable of creating chips for the microcontrollers used in the automotive industry. So the reason for the shortage of those is a lot more complicated, and has to do with a bunch of reasons like lack of raw materials (chip manufacturing requires pure monocrystalline silicon which is also in short supply, and what there is has mostly been redirected towards higher value chips) and decreasing production due to lockdowns. But the biggest reason is that at the beginning of the pandemic car manufacturers halted production completely, leaving many of these small fabs in shitty situation where they had to either close down or find other customers. So now car companies are trying to restart production, their old suppliers are reluctant to do business with them because they have shown themselves to be unreliable partners. Using CPUs instead of microcontrollers isn't going to help with this, unless you want your 50 cent chips to cost 200 bucks. And microcontrollers still cost a lot less than that, but automakers aren't willing to pay a higher price than what they are used to. The reason for that is that contrary to what they say, car manufacturers aren't in a rush to ramp up production, because in these uncertain times they aren't sure if they will be able to sell the cars they make. But admitting that would make their industry look less compelling to investors, so instead they blame everything on the chip shortage.