I don't always assume that anything that the powers that be do makes a whole lot of sense to be honest
On the island they are very effective at closing holding areas. Some river are not even worth fishing, because the open sections of the rivers simply do not hold fish, the fish shoot right through and only start holding in the closing sections.
If you don't believe me, or the "powers that be" that made the closures, you should come out and try it. They aren't dumb and they know where fish will stage.
I have found this years steelhead run is either a late start or just a bad run in general. From the rods I know who are daily fishers, in past years getting many fish to shore every year by this time.
Lastly... as far as what others have been saying about poor returns.. It could be possible they are just missing the fish?
One of my buddies had probably his best December ever, and I would say has been consistently hitting fish.
I went out for a total of 8 hrs when I was back home over the Christmas break and managed a wild on boxing day, so I figured it wasn't all that bad. Got lucky I guess.