You are incorrect. See my other post with a link to the clear exceptions baked directly into the law.
If what you said were true, then he literally would not have had an affirmative defense to plead at all, which is plainly wrong as the final order specifically notes his pleading of 2 affirmative defenses.
You can find these analysis of those affirmative defenses by reviewing the sections of the final order starting at 19
"by [critiquing an engineering formula] and submitting the critique [...] to members of the public" [...he...] thereby engaged in the practice of engineering [...] specifically, traffic engineering [...and thus] violated ORS 672.020(1), 672.045(1) and OAR 820-010-0730(3)(c)".
I agree his affirmative defenses are inadequate, but I'm not taking issue with the analysis of his defense. I simply am pointing out the justification used in Paragraph 14 is concerning. ORS672.005(1)(b) is way too broad.
[0] - https://www.scribd.com/document/346354146/mats4#from_embed [1] - https://www.oregonlaws.org/ors/672.007 [2] - https://www.oregonlaws.org/ors/672.005
You could be right if that false claim hadn't happened. But it did, and everything subsequent has to be evaluated within that context. Think of the difference between global and local variables, and the sort of bugs you get if you ignore scope rules (I'm guessing you're a coder, ignore if that's not the case).