I feel like the phrase “design principles” is a little overloaded here. Students studying architecture, graphic design, art, industrial design, interior design etc. learning about these principles. These include principles such as “unity, isolation, harmony, order, similarity (and other Gestalt principles), simplicity, etc.” There are many. These principles have been around long before you and I were born. I wonder why you (and others) feel the need to broaden the definition or even hi-jack the term “design principles” and use it to describe something else. Why not just call it Ux Principles. of which, design principles are simply a subset? The design principles I learned about and have used throughout my career are firmly entrenched on the tip of your pyramid (though some may percolate into the lower layers). I feel that overloading terms can be confusing to those of us (and there are many) who have come into Ux from traditional design fields such as those I mentioned above.
Putting that issue aside, I appreciated the article.