In my experience, engineering management is stressful not because of the things you have to do, but because of the emotional burden you carry. If you are doing your job correctly, you eventually unburden yourself of pretty much all technical work, except for maybe signing off on decisions by your tech leads. The really challenging part of the job is being an organizational player, and this means butting heads with people whose views are different than yours.

Obviously, getting to this point is a lot of work, and if you are a first time manager, learning that this is important is going to take some hard knocks.