I can't recall who originally put the content out (maybe @leavingweakness or @guerillachemist, not sure), but I read a post about lion's mane (particularly Host Defense) and why fruiting body was superior. Here's an article below. Yes, it's from the same place I buy my lion's mane, but it's the same info that was shared previously.
"With mycelium on grain mushrooms, you are essentially getting a lot of ground rice with low potency mycelium. Fruiting bodies give you nothing but the potent, effective, concentrated compounds present in the actual mushroom extract."
The realm of mushroom extracts is filled with a growing divide between those who prefer whole fruiting bodies and those who prefer mycelium on grain.
nootropicsdepot.com