I'm not sure that you could say all these people were continuously at the cutting edge of technology. Edison was very creative and self educated, but actually his lack of formal knowledge sometimes worked against him as he used hard work, trial and error. Curtiss did spectacular things with engines and aircraft, but in later years worked on non-aircraft projects even while Curtiss aircraft was flourishing.

The extreme of either position is not good. A IT pro and IT manager are NOT the same job and don't require the same skillset. A manager should have a good working knowledge of technology, but if he or she is a good manager, they will select good experts to provide input and advice.

A good hospital manager does not need to be a top surgeon, indeed does not have to be a doctor at all (though does need to be well versed in medical practice).

I'd much rather work for a good manager who was not an IT pro, than an IT pro turned poor manager.