Happy Vegan Couple

I have heard a number of whole food, plant-based doctors advocate that WFPB eaters should avoid using protein power, even plant-based powders.  Is there any research that anyone can cite showing negative effects of using plant protein powder?  I have plant-based friends who say they feel sluggish and tired when they don't take the powders. I ask if they are eating their legumes regularly and they say yes but they still feel they need the extra protein, typically pea protein.  Should one be concerned about their kidney function if they are taking in some plant protein powder?  Is there an amount that would be considered likely safe and not to worry about?  Is this a big deal or not?  I hear so much pushback on the advocacy of NOT eating it, similar to the pushback about NOT using oils. Interested in what Dr. Carney and others have to say.