People are afraid to do work on cars (and mains wiring, and plumbing) because even though the work is relatively simple the consequences for fucking up are so severe (severe damage, injury, death, etc). That's most of the reason they pay someone else to do it.

For the vast majority of software that isn't the case at all.

Most people don't understand computers and do not even know what is dangerous and what is not. They won't suddenly become vibe-programmers lest "AI deletes all of the personal photos and will send them somewhere".