On raw milk, i believe the primary benefit is that it is unhomogenised which makes the texture quite different (creamier) and fattier. Also heating the milk does not kill all of the bacteria and enzymes. However, as i said above and in the article i have never tried raw milk and i also said “apparently” which i meant to signify that i got that information from someone else so i do not know much about raw milk yogurt making.
I am interested to hear that you don’t heat new milk - do you skip the heating entirely, or do you mean you only heat it to 51C? It would be nice to not have to boil it.