The article is interesting, but I find his position that loading crawling defeats the purpose of it to be gratuitous assertion ...
I think that's being a bit harsh on the author. He feels that the best place to load things is when we're vertical or at least when we're moving between horizontal and vertical. That's an OK opinion to have, IMO.
Something I've mentioned here in the past, this time _my_ opinion, is that while we need to be able to move in multiple ways, none of us need to load all of them - one can become plenty strong for most purposes by loading a few, well-chosen movements/patterns and just making sure you can do the rest of them unloaded. That, to me, seems Brandon's argument, that we crawl unloaded and we don't want to lose that ability, but there are better choices for most people in terms of adding load. Again, IMO, it's a reasoned and reasonable approach to take.
TL;DR
I've watched Ed Coan talk about how he tried to strengthen everything he could, and for someone whose career is competitive powerlifting, sure, I think that makes sense. But then there are the rest of us. E.g., I happen to be so busy with my work and family life at the moment that I'm having a tough time fitting in even my relatively minimalist training. I can say with some certainty that, for myself, putting something heavy overhead with one arm, paired with picking up something heavy from the ground with two hands, and both while standing, has done wonders for me and is pretty much all I need.
There's a Bruce Lee quote about not fearing the person who's practiced 10 different kicks 1000 times each but fearing the person who's practiced 1 kick 10,000 times that also resonates with me in this conversation. Loading every basic human movement pattern is, for me, like practicing 10 different kicks instead of 1. Sure, it's more complete, but is that sort of more complete actually better? And in the context of the lives of busy adults who aren't bodybuilders or competitive strength athletes? Personally, I don't think it is.
JMO, YMMV.
-S-