As a some-time lifter, the idea of totally optimizing plate changes begins to feel a bit like taking the escalators up to the gym entrance where there are stairs right there[1]. After a couple of years of attempting what the author does here, it finally occurred to me that moving around heavy weights was the whole point of the exercise, and plate-switching was just a different move. Efficiency didn't matter, I was using my body and building strength. Shout out to people who are pressed for time and want to get their workout done in a small window: You do you, just don't hog all the weights and not put them back on the racks.
1 https://medium.com/@nessasaurus/only-in-america-fe7d2d5d461e also, I understand there are legitimately people going to gyms to exercise who may not have full use of their legs.