I believe a part of the actives oxidize during the drying process. For long term storage at room tepm, getting them cracker dry is highly advisable. I have lost batches to weird mold before. I personally would not overdry them, but have no hard data to back that advice up. But the less exposure to heat and air the better i would assume.

Oh crisp mushrooms also have the advantages of beeing very easy to process with your favourite weed grinder. Quick & easy powder to use for lemon tekking