Psychology and other social sciences are too multi-variate to speculate on, and the HRB exists so that we don't commit atrocities in the name of properly isolating variables as we poke at the black box we call the human mind. You're never going to get anything right, but we should definitely be referencing surveys of studies instead of single studies. So there's at least one point there for appropriate rigor. Not getting the interpretation of those studies right definitely seems unethical, but so does all of the misconduct stuff Van Der Kolk has been mired in.
It's a disingenuous argument to say that your body doesn't change from a traumatic experience, or that stress doesn't express itself through the body sometimes. It's also problematic to say that because it happens to you doesn't mean you can't work through it and learn to manage it or even control it. What I gleaned from the book is that if I have a physical sensation that I can map to stress or a past experience of trauma, I can understand it, label it, and grow from it.