I think, I now found the issue in "Side perspective". I took me quite a time, to unknot my brain, which was twisted by this misleading, oxymoron/term "Side perspective".
Preface:
Perspective is a one-way/non-reversible, non-iterative (think about this!) function, geometric construction, a projection.
With this and various threads around here, my personal conclusion is, if you cannot show/proof your point/issue in real world, perspective won't help you neither!
My "enlightenment" came with the 3rd video from zorbakim, when he applied his "Side perspective" on this "twisted tower" video.
He started to calculate multiple distances and heights applying his "Curve" from his theory and than in another step showed us views for this mangled distances and heights.
So what's this? In easy words you could say, he is applying perspective twice. Or better 1.5 times, as he only mangles heights in the first step.
That's another hint: Perspective affects the appearance of all 3 dimensions, not only the height of objects. So distant objects not only appear less high, they also should appear less wide, in both of the remaining 2 directions: width and distance.
In other words the "process" goes like this:
Plot heights of objects in "Side perspective": That's apparent, perspective hight against real world distances.
Now apply those heights to the real world objects. I'm still searching for a term describing this outcome: An intermediate view or an "alternate reality"?
Construct the final view by applying "classic" perspective...