1911s originated in a time when skilled labor was cheap and machine time was expensive- the exact opposite of where we are today.
Even the WWII 1911s were not 100% drop in and what ever level they did achieve was an intentional choice at the expense of accuracy.
It is absolutely a century’s difference in tech and design philosophy.
Take guns out of the equation. Even 50 years ago cars required much more tuning and maintenance than they do now. Tune ups every 15 to 20k miles etc are a thing of the past.
If you are fitting parts to a Glock you are either doing something wrong or doing it for an aftermarket part because you want to.