Actually if your hair is porous, as yours may be since porous means it has holes in the cuticle, which often occur from heat, dye, or just naturally, it needs protein to fill in the holes. Protein will make hair stronger, perhaps thicker only in the way that those holes will get filled in. Some people say it makes their hair thicker. I think it just makes it healthier and bouncier so it looks thicker, but that's just me.

Protein itself is not moisturizing, but if you fill in those holes that the moisture is escaping from, then you maintain your moisture longer. It's always a balancing act to get the moisture/protein right for happy hair.
FIA: 2b-c/f/i, normal porosity/elasticity I think?

Current favs:
lo-poo: Giovanni
Co-Wash: V05 Kiwi Lime
RO: CJ Beauticurls,
LI: Ouidad Botanical Boost
PT/DT: Emergencee, Biolage Condish Balm
Stylers: LALSG, Aussome Volume Gel