[orwin]

It's likely this particular issue is from a lack of quality control, and you cannot blame that on 1997 Boeing.

Quality control degradation in my experience and from stories i've heard are exclusively the fault of bean counters and exec pushing for cost cuts (unlike design flaws where the engineers share the blame). I've heard a story about an industrial machine amputating someone because the new joints couldn't handle the pressure (in france, pre 2019, i don't have the specifics). The maintenance guy wanted to replace the joints with high quality one (like the original were), but they were deemed "too expensive" so they bought new joints at half cost, to gain 10€ on the maintenance of the 400k machine. Less than a week later, the machine broke, someone lost an arm or something (don't have specifics), and a new machine had to be shipped and given for free, i don't know who paid the the amputated guy.