I do not find the to be the case at all. "Protein rich" for me is anything with more than one protein.
Update for my post above: I have found CJ Daily Fix to be the perfect protein boost when I need one. It's a cleanser so it is not on my hair for any length of time. It has one protein in it (plus horsetail near the bottom of the list). It seems to give my hair the perfect dose of protein when it needs it - I would say that is about once a week or so.
remember, with all advice or suggestions for your hair, YMMV!!
2b wavy, medium texture, low porosity, med-high density. Protein finicky.
Cleansing: DCNP, every 4-5 days (occasionally use CJ cleansers).
RO: CJSC, occasionally use JCDC
LI: KCKT or CJSL
Gel: KCCC, CJCIAB for 2nd day hair (sometimes third)
Heat is my friend: warm water rinses, steam caps, and diffuse dry. I love CLU cloths and my Denman.