Dried mushrooms are better than fresh when it comes to nutrition: 

Concentrated Nutrients: Drying mushrooms removes water, which concentrates their nutrients. This means that dried mushrooms have higher levels of vitamins and minerals per gram compared to fresh mushrooms

CIA Chef/Mycologist Doran Handman 

Chef Doran has been passionate about cooking, since the age of seven.

Boost in Vitamin D:  

Dried mushrooms are an excellent source of vitamin D, which is essential for bone health and immune function. When mushrooms are exposed to sunlight or UV light during the drying process, their vitamin D content increases significantly. This makes them a fantastic dietary source of this important nutrient, especially for those who may not get enough sunlight exposure.