wikipedia has the answers. tl;dr it sounds like both of those things: the reserve was in debt and was depressing the market for helium.
A public service (which is what a federal stockpile IS) cannot be in dept.
Can't wait until "fiscal responsibility" types are trying to sell off the justice department to the highest bidder because it "is in debt"
but that's different to being in debt. a public service can absolutely be in debt. it's given a budget, and if it fails to operate within that budget it goes into debt. that might mean the budget is too low, but there's always a point where a service is no longer worth the budget it would take to keep it operating. (not making a judgement on the helium reserve - i really have no context for how necessary or useful it is)
> “To put this discovery into perspective, global consumption of helium is about 8 billion cubic feet (BCf) per year and the United States Federal Helium Reserve, which is the world’s largest supplier, has a current reserve of just 24.2 BCf,” said University of Oxford’s Chris Ballentine, a professor with the Department of Earth Sciences.
I’d note this is only enough for 7 years of consumption. I’m not sure what kind of game changer that is.
Both figures absolutely pale in comparison to how much we throw out because it's not profitable but the fossil fuels it's in are, but that's nothing new.