Why aren’t smoothies protocol?

I am surprised to see smoothies on the ‘avoid’ list in the stop overeating workshop. If a smoothie has approved ingredients, is it the blending itself that’s the problem? (Because we didn’t have blenders back in the good ol’ primal days?)

My favorite smoothie includes pineapple, blueberries, coconut (pure 100%), oats, pea protein, and coconut milk. Aside from the pea protein, is this considered to be full of whole foods? Can I include it in my protocol?

I’m assuming that pea protein and all protein powders are OUT because they’re highly processed?