I think you missed the point of Raiders of the Lost Archives. It is not claiming anything was copied, it's simply complimenting the accuracy of the representation of the genre.
As the creator says, in the Intro:
Shot-by-shot comparison of "Raiders of the Lost Ark" vs. scenes from 30 different adventure films made between 1919-1973. My love letter to Indiana Jones and the films which served as inspiration.
And says in the comments:
It's indeed puzzling why so many people misinterpreted the video. Maybe the wording of the intro? They don't understand homage? Who knows but, as you said, the written description calls it a "love letter".