> It might be that the manufacturer moved to higher priced chips and retired the old fab equipment.

That's exactly what happened. Square footage in a fab clean room is $$$$$$. If there's no orders coming in for an older process that shit gets chucked and replaced with new equipment running modern nodes faster than your mother can suck down a hot dog. And automotive was the worst offender at being dead stuck on old processes, because retooling their own integrated components is money they hate spending.