I had to go to the dealer for wiper blades, no one else had them and they were on backorder. No problems with our power distribution control module. But as for maintenance, it literally has needed none since we bought it.
There’s one heck of a lot of parts for late model ICE cars that you won’t find at e.g. Autozone either.
The commodity crap like GM alternators for any 1970s through 1990s GM product? Sure. Brake pads and other common wear items for nearly any mass-produced car of nearly any age? Sure.
An XYZ computer module for a 2024 Toyota Camry? Little chance. An XYZ computer module for a 2024 low volume production car like a top of the line German or Italian ICE? Zero chance.
I didn’t thoroughly read the whole thread, but I’m surprised I didn’t see one of the main reasons: The dreaded check engine light! Around these parts, the auto parts store has the diagnostic code reader and can get you a print out of the latest code (also shows previous codes that might not trigger the check engine light).
I just had to do this recently on my old Subaru: P0420 - Catalytic converter. I wish it were an O2 sensor, but the exhaust is rattling a bit so I’m guessing it is the more expensive part that’s failing. Darn.
Headlights used to be round. 7-11 had them, along with 1157 brake/turn signal bulbs. Fit many makes. Anti-Freeze was green. Oil? 10w30. Cars and trucks are much better now, but a great many things were a lot easier as well as less expensive.