I once had a bottle of pure PAO HVAC lube. It has no additives and was water clear. It would be useless as engine oil though.
With multiple high quality base oils available and the newer Ashless antioxidants being used, the difference between GTL, grp III and PAO are being erased.
Are there better finished oils than others? I am certain there are marginal differences, since mOre research and expense goes into different tiers, you can see that on the shelves.
We can enjoy and learn of the advances, or we can agonize over details we will never learn.