Or are you saying that they knew, but somehow did not do it?
Not at all saying that they were incompetent. On the contrary, passenger planes today are IMO much more complex than one desktop computer loading a web page: passenger planes are a group of many computers doing safety-critical stuff in order to maintain a giant machine up in the air.
I don't see how one can say that software engineers don't really understand computers, but pilots do really understand planes.
I recommend reading “Flying Blind” for more detailed accounts of the precursor lion air flight that almost crashed.
I just did not find it fair to say "pilots know how planes really work, but software engineers don't know how computers really work". Both are waaaay too complex for one person to actually understand fully.
I wouldn't bet that most pilots know more about how the planes they fly work than software devs know about their computers. For one, most planes today rely heavily on computers. Do they teach electronics in "aviation"?