Car manufacturers want the part to be available for 20 years.
They don't want latest, smallest, fastest tech. And they don't need it either outside of the infotainment system. And it's BAD when it's a chip wired to the spark plugs.
The hiccup... Every car manufacturer has a different ECU, Brake Controller, etc. Potentially different ones for each make and model of car.
There are opportunities for standardization. However, the car manufacturers want to lock in repairs to their mechanics, their diagnostics tools, and their parts. And there are hurdles on regression testing for safety on things that often kill people.
Being pragmatic... an ECU that can handle the Bugatti 8.0 Liter W16 and the Wärtsilä-Sulzer RTA96-C should handle everything else on the market. Good luck getting the engine manufacturers to cooperate and standardize.
NXP and similar companies buy these old fabs for pennies on the dollar.
And it goes to hell when all the old fabs for sale are concentrated in one geographic area with climate problems and neighbor problems.
And the old fabs not for sale are owned by a company that's notorious for not sharing.