There’s no long term knowledge about fungus stuff once processed into these new forms.

Just to clarify that the fungus stuff is just mycelium. It is a totally natural product that is in this case foam-like. It is not processed, just dried at specific temperatures.

As they mention in this article:

these earplugs are made from Forager’s mycelium foam – and nothing else. This means they can break down in weeks to months,

“GOB’s earplugs are USDA Certified Biobased and entirely made from mycelium, a natural material that breaks down as easily as the produce you eat,”