Habitats have immune systems just like people. Mycelium is the bridge between the two.
Incorporating fungi into our lives and our environment strengthens the defense of the entire ecosystem, preventing disease vectors from emanating out.
For example, if I live in the middle of a polluted industrial site, I am a reflection of that environment and I am likely immunocompromised. This makes me a threat to the entire biosphere because I could be the source of a disease or pandemic, I might need a lot of medical attention and resources, further affecting the environment.
Mycoremediation essentially means the use of fungi to absorb, degrade, or sequester contaminants that have accumulated or been suddenly released into soil or water. Mycelium-filled drip filters can be used to clear water in sewage systems from from motor oil, roadside toxins, lawn and farming pesticides. I can drink chaga tea when I have a cold to boost my immune system.