Just the way it is, and I don't know what the solution is, if there is one.
It is the role of junior officers to stop the senior NCOs getting out of hand, but at the same time, any junior officer relies on his sergeant to temper theoretical knowledge with practical experience. A junior officer with minimal in country experience who tries to pull into line an NCO with a couple of tours under his belt is going to have real difficulties. I've seen it done but it's not without pain.
Usually, there isn't a problem, but if the's a cabal of bad NCOs, even just a couple, things are going to be made very difficult for the Lieutenant.