For a little bit of context, Robert Lang is what you could call a "modern master" of Origami. He's one of the author who promoted a "whole vision" approach to model design, using lot's of circle/square packing and a very scientific methodology. He's also the author of several books (and some software!) to explain how to design your own models using his techniques.
One of the reason the last model is a new scale of complexity might be that it somehow use "old school" techniques: There is now collapse, no circle packing, it's just straight traditional (hard!) folding from start to finish. Creating such complex models from the traditional tools is usually really hard. It also has a certain elegance to it that is often very pleasing.
In my experience models made from crease patterns tend to be rather boring. Yes, it’s tricky and menial to collapse them, but once you’ve done a few, you can fold all of them. It’s a mechanical procedure, so much that these designs are usually generated with a software called TreeMaker, pioneered by Lang himself: https://langorigami.com/article/treemaker/
I had no idea about the level of formal planning required to make these complex objects. It’s almost like a spatial algebra that’s being used and then the folding part itself seems to be a two step recipe.
As I understood it, after (1) planning out your design you then (2) create a flat set of pockets with as many pockets as you need appendages, of appropriate sizes, before (3) extruding those pockets out into limbs, antennae, wings, and eyes.
Having it explained visually, it makes so much sense. A bit like a chef doing mise en place before then constructing a dish. Absolutely fascinating.
If you want to learn more about this stuff, the guy in the video wrote a great book called Origami Design Secrets (https://www.amazon.com/dp/1568814364/). It's certainly still the book about origami design.
For something that still touches on some of this stuff but is more beginner/child friendly, I'd recommend Jun Maekawa's book Genuine Origami (https://www.amazon.com/dp/4889962514)
There's also the OSME books (http://osme.info/) which collect origami related papers.
Robert J. Lang has been an avid student of origami for over fifty years and is now recognized as one of the world’s leading masters of the art, with over 700 designs catalogued and diagrammed.
Haven't watched the video yet, but I was pleasantly surprised to discover that David Huffman (of Huffman coding) was a pioneer in the field of mathematical origami when I attended an exhibit of his works in Santa Cruz in 2012[1]. Quite stunning to see in person.
Robert Lang and Erik Demaine were also featured, IIRC.
One of the reason the last model is a new scale of complexity might be that it somehow use "old school" techniques: There is now collapse, no circle packing, it's just straight traditional (hard!) folding from start to finish. Creating such complex models from the traditional tools is usually really hard. It also has a certain elegance to it that is often very pleasing.