About two years ago, there was a lot of interest in pH of certain products. Some of use were measuring and reporting. At that time, I made an observation, when a product called Dr. Bronner's Shikakai Rinse was being discussed. It ended up having a pH of 3! The folks who liked it had coarse, porous hair. The people who seem to prefer cleansing with soap bars are low porosity--maybe low porosity (and possibly fine/medium) can do the more alkaline products?? And the other end of the continuum can do the more acid products.

It's speculation, but an interesting question to look into. Hair products are supposed to be in that 4.5-5.5 range, unfortunately all of them are not.
3a (Corkicelli), highlighted, fine, low porosity

HGs: Anything Sevi; Curly Kinks Satin Roots, Curlycue ReNew and Coil Jam; homemade FSG and okra gel; soap bars; UFD Curly Magic; Botanical Spirits Jellies, CJ Repair Me, Aloe Fix