Are managers worth their pay?

I have heard it all now, today I was told that some managers can't even switch a computer on and think that's OK. They use their age as an excuse for lack of knowledge. That is like saying I don't need a pen and some paper to write a letter. What are we paying them to do? Yesterday I mentioned admin staff and how poorly trained some of them are, now it's the managers. Not all I must add. If I said that 55K was a wage I heard, what would you say? I would expect them to be very IT literate and very good at their job, with vast experience in their field. But no, in this case, no project management experience, but in a project management role, not IT literate but in a job where IT skills are necessary and worse still, not good at their job either. How frustrating it must be for the admin support team, who probable do most of the work but get none of the pay and none of the credit. Who is going to bring these people down to the levels they should be at. Promoting people to get them out of the way has to stop. (I am talking about the public sector here) What do you think about this how can we change it?