So is Paul Stamet’s Brand Host Defense Garbage in terms of Lions Mane?

I would imagine it is to concentrate the nutrients to allow for better propagation of their spores. Reshi spores have a ton more triterpenoids in them than any other part of the mushroom. Like a massive amount more. Then you have ones like chaga, which don't form fruiting bodies, but actually just form a big mass of mycelium called a sclerotia. That sclerotia starts to pull nutrients from the birch trees during fall/winter, which sustains it through the summer. The whole purpose of any living thing is to grow and reproduce. So concentrating nutrients to be able to best do that, or to make it attractive to animals like in the case of fruit on plants, is an evolutionary advantage that helps that organism spread it's genetic material as best it can.

Correct me if I'm wrong, but I understood the organism as a whole is mostly mycelium. Why are the fruiting bodies considered more potent or the main desired product?

That really depends on the specific mushroom. The fruiting bodies of lion's mane have much more mass than their mycelium. Then you have ones like Wolfiporia extensa and Inonotus obliquus that are only mycelium; both forming sclerotia. One forms on birch trees and the other forms underground. Then you have things like truffles, which form fruiting bodies similar to a sclerotia underground next to tree roots. Have you ever heard of Philosopher's Stones? That's a psychedelic mushroom that forms a truffle-like sclerotia, but also forms fruiting bodies that go above ground. The variations in fungi out there is immense.

Again, I am not saying mycelium has no benefits. There are certainly interesting things in the mycelium, and often in higher concentrations than the fruiting body. It just depends on the mushroom. However, my issue is growing mycelium on rice, not letting it ever grow a fruiting body, then grinding the entire mass of rice and mycelium up and calling it a mushroom. It would be like me advertising and selling you a pine tree, but then delivering a big mass of soil and roots. My other issue is the lack of peer-reviewed scientific evidence for the claims the mycelium on grain vendors are making. Also, the constantly changing story by them as people start to question them. Furthermore, they standardize to polysaccharides, which starch is a part of. They grow it on rice! Of course there is starch. It's scientifically dishonest to standardize something to something you know is a confounding variable in the growth medium you are using; especially when you grind the growth medium up into the product itself! Also, we have tested these products in the lab. This is why I am so direct with this. I know what is in these products. I am not blindly making claims. I have scientific evidence that it is mostly starch, and that the beta-glucan numbers are insanely low. The science just does not add up, and the scrambling Paul Stamets is doing to try and sway public opinion just makes it more clear to me what is going on. To top it all off, mycelium on grain is CHEAP! It's sooooo cheap to make, but Host Defense is super expensive. It's absolutely insane!

I am all for scientific advancement and improving our understanding of the science behind things. That's why I am doing what I am doing. However, the science has to make sense. There has to be evidence that leads us to a common scientific conclusion, or it is our duty to question the claims. That's the very thing that makes science, science. We need evidence that we can go out and reproduce the findings of; evidence that makes sense. If Host Defense had the science behind them, we would have that evidence. We would not be sitting here discussing how respected or likable Paul Stamets is. We would be discussing the facts of the evidence.