Of course laying out a year or two never hurt a population that I'm aware of.
I pushed hard to lay out our deer season for 3 years here at home, it needed it really badly. The folks that hunt around were flat to greedy to do the herd that amount of good.
Thankfully we finally put a decent antler restriction in and that slowly built it back up. It could have been done in 3 years of no hunting, but no one would go that.
There are underlying issues with the caribou herd, from what I hear anyway.
And shutting the season will hurt the guides.
But it won't hurt the herd.