Markets can predict future shortages and rise prices in anticipation. Nobody wants to sell cheaply today if they can get more than the prevailing interest rate by sitting on the resource. And if we are talking about really long time frames where the risk/reward ratio is not clear, why should we assume the governmental decision is better than someone who has financial skin in the game? Maybe the conservation decision will actually be a bad outcome, conserving at a great present cost something that will be worthless in the future.

Global warming and other environmental problems have nothing to do with this. The environment is a shared resource so market participants have no incentive to preserve it, on the contrary, they rush to "use" as much of the common resource as possible and maximize present gain, before someone else kills the planet and there are no more money to be made. The solution there is to tax the externalities and transform the public resource into a private cost that must be minimized, thus preserving the resource. Helium is not such a public resource, it's private to those who have it, produce it and store it.