Great article. I also suggest
Shooting Illustrated - August 2022 [30 - 31] (nxtbook.com) and then continued on page 75.
The very things spoken of in there are the very lessons I've learned myself and why I personally only have one AR with two uppers, identically configured except for caliber specific differences. You can have a hundred thousand guns and suck with most of them, or shoot one gun a hundred thousand times and become it's master.