||I took a quick look at the article you're talking about by Hara Ra. He states that because plastic allow oxygen to pass through it, mushrooms stored in plastic bags will be exposed to oxygen and will lose potency over time. This is true. He suggests using freon as a gas to stop this process. This solution seems unnecessarily complex.|
Any method which keeps oxygen from contacting the mushrooms can help preserve potency, so in theory this sounds like a plausible method. But, freon has been banned in the U.S. for use in air conditioners because of its impact on the environment (ozone layer). I would guess that's it would be difficult to find a can of freon these days. If you choose to go with a freon method, make sure to get 100\% contaminant-free freon. I wouldn't trust that a can of dust-off would be pure freon without further checking with the manufacturer.
A much simpler and safer solution is to simply use glass. I can think of no reason why anyone would want to go to the trouble of working with freon to duplicate what can be achieved with glass. A glass jar with a fully sealing lid (like a mason jar) will not allow oxygen to pass through. Fully dried psilocybin mushrooms stored in airtight glass containers even at room temperature should last for years. Pack the jar tightly so there is as little air remaining as possible.
As Hara Ra mentions, another variation is to use dry ice to replace the oxygen in the jar. See Preserving Mushrooms with CO2 for more info.