If code written by a "Senior" Engineer is unreadable/unworkable by someone with less experience - that is 100% on the writer. Don't enable ego-fueled programming, best to either do as the article suggests or bring in some actual more senior engineers who have already learned that code is read 10x more than written, and should be optimized thusly.
The wikipedia page literally lists them as a sponsor of a team:
"From 2006 until 2018, Oettinger was the official sponsor of Rockets, a professional basketball club based in Gotha. The Rockets played as "Oettinger Rockets" in Germany's first distribution, the Basketball Bundesliga.[5]"
This is.... quite strikingly poorly written - no research even by self admission on most of this: "The complexity graph is not based on any research, it simply reflects my own experience working with Object-Oriented, Procedural and Functional Programming."
We all can say negative things about any paradigm or pattern - but this is quite a hit piece. Proposing "functional programming" as a replacement is quite ignorant of many (vast majority?) of platforms and realities of programming different kinds of software (especially event driven).
Functional Programming is notoriously hard to ramp engineers onto, or for folks that join a team with a codebase written as such it can be extremely difficult.
Maybe I should write one; "Medium - the Trillion Dollar Mistake"