First is true,
not sure on second. I'm not sure what voltage limits TSMC has but I suspect they have multiple processes, which may include high voltage rulesets. High voltage and/or high current, that limits the ability to use small geometries. But not all auto IC's have to be 12V or 48V tolerant. I'm sure the memory chips in the ECU and/or radio are not.
But yes, auto IC's can be very niche. Need to do limited things, but real time, not as gated by OS. But they also keep upping what the chips need to do, and doing it with less (power or cost or size). Voltage buck/boost, LED drivers, gate driver, motor driver--the list goes on for high voltage and/or high current. Lots of cool devices in cars.
Need to make sure we in-shore PCB manufacturing too. There's some good shops here already, but I'm not sure where the raw PCB materials (cores, prepregs, foils, solder mask, etc) are sourced from. And most of the chips go onto a PCB when used (most not all).