> I can't imagine that people who actually work with software would trust these things.

There's a whole different genre of software when it comes to life-critical or mission-critical software. The sort where a bug could kill people or cost millions of dollars. Real engineering. Used to work on OBOGS which let fighter pilots breath. If you have a bug and the thing stops generating oxygen, the pilot has about 30 seconds to notice and pull an emergency lever to switch to the emergency tank. DO-178 would be the super-fun process to make this sort of software. And yes, you have to start worrying about stray cosmic rays flipping random bits in your memory. Lots of CRC checks and watchdogs and heartbeats. The time to reboot a system is important if the pilot can't breath in the meantime.

But if you ever.... drive a car on cruise control, ride an elevator, get an X-ray, then you've trusted your life to some lines of code.