I have to agree with the overall sentiment here....and I am sure that anyone with experience can tell their own war stories of dealing with a professional "manager" that thinks they only have to manage people and don't need to know anything about the job those people do... I can't stand those as I don't find it to be true.
I used to be the first person to bring up the past examples of someone being "promoted out of their sphere of incompetence"... but I was lucky enough that whenever I came across those people, they had always managed to actually end up as good managers... they had the mindset for management much more than they were technically capable of delivery.
For myself I have recently changed jobs and moved from a management role, back in to consulting... and as much as I complained about dealing with the HR stuff "because I'm a techie"... I now find myself the first person raising his hand and volunteering to help set up a brand new graduate program with personal mentoring and career guidance for the first time for my current company.... I now see the things I can offer beyond just the technical and find that I want to challenge myself in those areas... (and for a while longer keeping myself current on the tech and walking the walk as a consultant)... I'm sure at some point in the future I'll get sick of dealing with clients face-to-face and I'll end up back doing an internal management role...
but for now.. I have my nerd propeller... so let me code and test in peace :-)