Why does senior management at these companies think that programmers should be managed by people who know nothing about programming?
A good manager can be good without knowing about programming. Right now I'm on a mixed team that is managed by a guy who has no background in programming. He trusts his people and delegates a lot of borderline managerial tasks, such as prioritizing technical work and evaluating the success of projects, to senior programmers. Apparently it's a viable way to manage programmers, because it works well for us. The manager lets technical folks make the technical decisions and backs his tech leads in cases of disagreement. It would all fall apart if he stopped trusting the judgment of his technical leads, but when management doesn't trust the judgment of their senior people, the situation is probably FUBAR anyway. Ditto if the senior technical folks behave unprofessionally -- it's a FUBAR situation until they act like adults or you get rid of them.
Domain knowledge can help a constructive manager become a more valuable asset for his team, but any competent manager can at least learn to get out of his team's way and provide support in small ways. If a manager is an obstruction to getting work done, then he's a bad manager, and domain understanding won't turn him around. It might even make him more effective at being an obstruction.
A good manager can be good without knowing about programming. Right now I'm on a mixed team that is managed by a guy who has no background in programming. He trusts his people and delegates a lot of borderline managerial tasks, such as prioritizing technical work and evaluating the success of projects, to senior programmers. Apparently it's a viable way to manage programmers, because it works well for us. The manager lets technical folks make the technical decisions and backs his tech leads in cases of disagreement. It would all fall apart if he stopped trusting the judgment of his technical leads, but when management doesn't trust the judgment of their senior people, the situation is probably FUBAR anyway. Ditto if the senior technical folks behave unprofessionally -- it's a FUBAR situation until they act like adults or you get rid of them.
Domain knowledge can help a constructive manager become a more valuable asset for his team, but any competent manager can at least learn to get out of his team's way and provide support in small ways. If a manager is an obstruction to getting work done, then he's a bad manager, and domain understanding won't turn him around. It might even make him more effective at being an obstruction.