As a long time IC turned EM; in my experience non-technical EMs are alright, technical EMs are great, but pseudo-technical are the most dangerous both to the company and their direct reports. It's like the midwit meme, but in real life.
Perhaps the belief is somewhat self serving, but I've seen dozens of examples of good non-technical EMs and good technical EMs, but never a good pseudo-technical EM. The pseudo-technical ones are so jaded with technical work that's palpable.
Also, reminds me of the famous Elon Musk quote[1]:
> Managers in software must write great software or it’s like being a cavalry captain who can’t ride a horse!