"It's not my will, it's the will of the bugs in my butt!" yes, very "relieving."

I kid, ;) but I see your point. The idea that you might, say, struggle to resist candy and sweets and it's because some population of your gut biome is fighting for its life if you don't eat sugar... makes sense.

The idea that "I just cut sugar out for six weeks and my willpower to resist sugar went through the roof" ... not because your willpower changed, but because you killed that part of your gut biome.