I think people believe planes are made by a bunch of academics smoking pipes in an ivory tower, because the most precious thing in the world flies on them: people (a rather Western point of view when compared to Russia where a human life just exists for the meat grinder for the glory of the empire (or whatever it is that they made up this year)). As such, they think there is some kind of perfection going on (no doubt they believe their sky scrapers are also able to withstand the impact of an airplane (guess that didn't work out either)), which is obviously not the case. Perfection in this world exists, but anything complex made by average people (meaning everything made out of anything that is not fully digital (and any consumer digital product doesn't fall under this)) is going to be very much not perfect.

In short, I think it is not unusual.

Boeing claims to have adopted https://en.wikipedia.org/wiki/AS9100, which in 2015 already specifically mentions human factors as something they need to take into account, so somewhere there needs to be a document, which describes what happens when some idiot uses a tool that they should not be using for installation. That means that they have had at least 9 years to fix such issues and they probably have had continuous improvements over that time (they do have QA people and surely they must be doing something, right?). If Boeing was a full on circus, there would probably have been more serious problems.

If you look at the regulations, there should be processes for everything, but perhaps the "process" is that they can jump on some wing and that some machine scans it for problems afterwards. That too is still a "process". It would be a problem, if the process is to use XYZ Corp Screwdriver 5000 to install Magic Part and they didn't have that screwdriver and instead decided to just use the Tarzan method.