Yeah... I've encountered thousands of software bugs in my lifetime. Including with critical car systems like the gas pedal on my Toyota.

I don't know anyone with a passenger car who's ever had the steering wheel linkage break to the point turning the steering wheel stopped affecting the wheels. I like the failsafe there. Hopefully at least the brake cylinder is still connected to the brake pedal mechanically?

But firmware doesn't rust and snap or burst, like I've experienced on other vehicles.

Cutting corners is cutting corners. Build cheap firmware or use materials with poor corrosion resistance and you get problems.

It's much harder (impossible, really) for a owner to mitigate against firmware bugs, though. Regularly servicing and inspection should prevent/detect the vast majority of major mechanical issues, not to mention than many are slow-onset.

A firmware bug just happens, and there's no way (as an owner) to detect it beforehand.

Software isn’t unpredictable. Issues that are known can be resolved. Unknown hardware issues are just as bad, and they do happen. Most safety recalls are mechanical in nature today.

Fly-by-wire systems in airplanes are way more complicated than cars and they have excellent safety records, which even improved as those systems became widespread.

The reason so much bad software exists in the world is because of the prevalence of people writing software without an accredited engineering education, licensing, or regulation. Software can be good if built to the engineering standards expected of any other engineering discipline.