Agreed, I can see fundamental flaws to many experienced peoples logic and knowledge, their suggestions often are missing key fundamentals. Often their ideas still work but they're either reinventing the wheel or overlooking something. Many things to them are relative, whereas it should be absolute (benefitting from past human learnings).
I mean it's on full display with social media, people these days are willing to chime in on things they have no understanding of and come to the wrong conclusions.
We're biased towards simplicity. But unfortunately, when you get better at things the small details and subtleties become more important. Literally by definition complexity increases. You can no longer ignore them and improve. Low order approximations will only get you so far.
The problem is we make these low order approximations, recognize that they (ideally) help and congratulate ourselves. It's just a matter of stopping too early. You see people say "don't let perfection get in the way of good enough." I don't think perfection is usually the issue, rather a disagreement about what's good enough. So sayings like that just become thought terminating cliches[0].
[0] https://en.wikipedia.org/wiki/Thought-terminating_clich%C3%A...