Transitioning to management is one of the more complex transitions you can make in your career, and I’ve been thinking recently about the mindset shift required to pull it off successfully. Actually, I read about inversion (see references), and started thinking about what themes were common among ICs (individual contributors) that weren’t able to make it work as managers. One issue kept cropping up as I went over past colleagues who switched and stumbled: they thought they were still in their IC prime.
I agree with the dysfunctions you presented (and love the IC Prime drawing), but I am not sure the first question you posed (i.e., Do you think your IC prime has peaked / is on the decline?) is likely to be helpful for ICs contemplating the transition.
If you're a PM who's just launched your biggest product, do you believe it's likely that you'd go from Thinking Big about that product to concluding, "Well, that's the best I can do. I'm past my prime." For someone to accurately predict (or admit) that seems unlikely to me.
What answer to that question would help the person make a decision? If the person concludes "Hey, I'm past my prime as an IC" does the person have the right type of growth mindset to be a great manager, to inspire and coach others to their fullest potential? Or, if they conclude, "Yeh!! I still have some IC Prime in the tank" what would encourage them to leave IC Prime, and pursue a different path?
In general, I think that question leads to a conclusion I see periodically among Engineers, and that is the belief that Engineering Manager is some sort of promotion from Staff Engineer--that the roles are points on the same continuum, rather than different jobs altogether.
For Your Consideration. The heart of a lawyer's job (in many cases) is brand management: drawing disparate threads together, spinning them into a new yarn, and asking outsiders to consider a different perspective: sewing doubt about initial opinions if you like. That would appear to have a lot in common with someone in marketing who is responsible for understanding customer preference, and helping people make the leap from one thing to the next. You can (maybe) move between those two roles, but I don't think you do lawyers or marketers any favours by suggesting one is a progression from the next. Similarly, if we position Manager as a "next step" for an IC--something you might do if you're past your IC Prime--I think you set up situations where the IC Prime dysfunction you describe is more likely.
I'd love to hear from other engineers what they wish were next steps on their career path that they don't see as available options.