True, but you can fix faulty software written by erring humans. Not so much with erring humans killing their passengers directly in numerous ways both completely new and well know for a century.
You can develop both, but one of them is constantly trying to self-implode. The software does not forget to run coded sub-routines, humans tend to ignore lessons learned. At the same time, modern-day SOPs are already well algorithmized. All that is needed is an operator who/that will follow the script without ommisions due to lack of attention, guilt inflicted denial of facts, and egotistic creativity.
Even if you did find a solid, proper material and built a pool of trustworthy professionals, they will go retire, seek out better pastures or you need to let them go at the next downturn. And you start over and over again.
One of the best advices for aviators you'll find appeared in a post from
hans brinker in the command upgrade SIM thread: "
Do not do anything surprising". Software is capable of achieving that, live people are not.