Sums up my entire opinion about minimalism and graphic design. Minimal color, minimal shapes... minimal talent for maximum effect. It's not worth $80 to learn the right spot where to put a rectangle.
It's like Mona Lisa vs. HN front page.
One is minimal and can be done with no talent and the other requires 10x more talent to create.
A designer is the same way, say you need a page designed, and they've been through this task so many times they know what works and what doesn't. The lack of knowledge and experience in this area only adds to the time it takes to create & finish something.
And so you're usually not paying a designer to throw a colored rectangle, you're paying them for the years they've invested in testing everything else.
The only thing a designer has to offer is speed. It's like someone who works at a fast food restaurant flipping burgers. You flip a lot of burgers... of course you get fast. You design a lot of simple templates... of course you get fast.
Here's a good example of minimalism to illustrate my point: https://qph.fs.quoracdn.net/main-qimg-8dfbbdd6a69a5f0e605e5d...
I get what this picture is trying to do, I get it's aesthetic. But I also know that almost ZERO effort was spent making it. Many "designs" have a less obvious aspect of this issue and I believe that this book is just dealing with issues that are more or less obvious.
But that's just my humble opinion.
People who contribute very little to society but get paid way more than they deserve.