I had a comparable impression from reading Cybernetics (at least the parts I got to so far) and other books on system theory.
I think cybernetics the practice / math is alive and well, even if cybernetics the name is mostly discarded. Take a look at Wiener's wiki page:
Wiener is considered the originator of cybernetics, a formalization of the notion of feedback, with implications for engineering, systems control, computer science, biology, neuroscience, philosophy, and the organization of society.
The right way to read that is that it's used in seven fields, not zero.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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