As I said in the comments above, the single most effective measure for reducing accidents would be checking for alcohol- or drug-influenced drivers. Those cause much more accidents than mechanical failures.

Yet even though "alcohol-locks" have been mature tech for five years, no car manufacturer nor politician dares to make it default, simply because there would be public outrage.

Also, stuff like brake pads or tires completely worn down already comes with basic safety features: both will cause the car to make relatively loud, screeching/rumbling ominous noises.

As a person who almost never drinks alcohol (that stuff tastes nasty) an alcohol-lock would just be a big annoyance.

Well, current-gen tech is. But an AI/camera based version that quickly checks your pupil dilation when you put the engine in gear could work just fine. It could also catch drugs other than alcohol.

Or you could do near-infrared spectroscopy built into the gear lever (this is already being pushed by the NHTSA, and will probably be in cars in a few years).

Or it could even have a selective alcohol-lock using current-gen tech that only triggers a check if alcohol is detected in the air circulating in the car.

Probably the most advantageous part of fully computerized cars will be DRM and part management. Like your printer which refuses to print black because the yellow cartridge (which is half full) is past its expiration date, your car will in the future refuse to drive because the dealer hasn't changed its oil with the DRM oil filter in the past 1500 miles.

Mandatory adherence to the OEM's maintenance schedule (and every appointment dealer-only!) is every car maker's dream.

Although you're right, they probably will just force maintenance at particular intervals, it would be nice if the car could do a quick self-test that, if it fails, it'll refuse to drive, or at least drive quickly.

Low tire pressure? Breaks not operating outside of acceptable parameters? Tires behaving strangely? It's manual or nothing at that point.

They would probably refuse to drive autonomously if it detects the maintenance period has been exceeded without being reset or there is some sensor or mechanical issue detected. But you will always be able to drive it manually in case of emergency.