I'm quite confused by some of the pain points that the author mentioned. For example, the Dolphin view switch icon - you absolutely don't need to click on the dropdown to change the view, you can click the icon itself and it'll change (and I'm pretty sure this is why the button is "two buttons" and has the divider next to the dropdown icon).
For Spectacle, regarding the extra mouse clicks - most of the functions include a (global) keyboard shortcut by default and for the few that don't, you just need to set one.
Floating panels: Whether you like the design of a floating panel or not is of course subjective. However the author mentions that you need to "aim like an idiot and waste your time hitting the 'floating target'" - except no, you don't. They can "slam their mouse into the screen corner" because the target zone for the applets extends below and to the corners of the screen. If you want to open the Application Launcher for example, you can "slam" your mouse to the bottom left corner and click - it will open. Same with every applet (I do not believe this to be something the applet controls, but rather the panel itself so it should work with any applet).
Kubuntu's "anti-user move" is not controlled by the KDE team. Not sure how much control Ubuntu spins have over their packages, but it is either a Canonical move or a move by the Kubuntu team - regardless, its not something the KDE team mandated (AFAIK they are not removing X11 support). The only thing the KDE team has done is make the Wayland session the default.
Regarding the bugs they've found, I hope they reported those on the KDE bug tracker.
This line in particular made me laugh a bit though:
... plus "simple" interfaces is NOT going to win the hearts and minds of the common people. That's not how it works.
Yes, it does. A "common" person does not care in the slightest that libmyfancylibrary was updated to version 1.2.3.4, I mean I'd argue they don't care in general about updates but I digress.