Oils are sold by performance level in the US. There is no regulatory body governing the composition of a synthetic oil.
Again, I have made this post before:
https://www.exxonmobil.com/basestoc...-ii-base-stocks/EHC50-and-110-brochure-v2.pdf
There are ways on the market for formulators to blend Group II/III based Dexos 1 approved oils.
I do not have an issue with Group III being labeled synthetic. My issue has always been with the Group II/III blend oils that are now capable of being Dexos 1 approved and are
probably being sold under disguised as house-brand full synthetics.
I agree that any Group II/III HDEO is superior to Group I from 30 years ago, but all of these things are relative to the engine designs on the market today.