I have no zero nadda experience with storing weed so I cannot even guess what will happen to weed stored for years..
Perhaps the weed industry has developed ways of preserving it. I don’t know. I imagine it will still be potent but also full of fungus mold if not properly stored.
But enough to supply the entire state for 6 years? That’s nuts. No industry stockpiles that much - well maybe the diamond industry does but that is a very tight cartel. It should lead to a total collapse in the market price for weed, which means collapsing weed tax revenues for the state. All that weed will either get diverted to a black market somewhere (perhaps even in OR) or drive the production out of state. Why would anyone want to pay to store for years that which you can create fresh in weeks? There is really no reason weed should cost more than celery, and when it is legal for anyone to grow a bunch of plants they are undermining their own tax-scheme. Which is fine by me, really.