There are best explanations to particular questions. Maybe C.S. Pierce’s pragmaticism works for mathematics too. What if Pythagoras (the old round Earth theorist) and Euclid had been Pyrrhonists and quailed from finding the right answer because no rational criteria can exist for regarding anything as best or more than a prejudice? Skepticism has it’s uses. It should remain until one has certain so far as possible. For example there aren’t many scientific skeptics of Darwinian theory these days though it would be wrong to not recognize that it is a nominal explanation and has deeper, transcending possibilities farther on.
Whether or not Locke was a Pyrrhonist is a very interesting question and issues that lead one to consider the relation of real and nominal essences in a quantum mechanics, or even Bohm-Debrolgian or Everettic context (of monism).
How can one ultimately differentiate monism from pluralism, and is pluralism necessarily temporal and phenomenal? Must one see deeper into any pluralist physics to comprehend a monism or unified field?
Is nominalism all that is possible for understanding things in-themselves, while realism and monism are too deep in a Kantian sort of noumenal for-itself behind the glass, darkly?
I suppose a Pyrrhonist could be placed with those of the Copenhagen Interpretation where the observer collapses the waveform quanta of the in-itself to make it a being-for-others.
Locke’s apparent preference for not looking farther than the nominal, or sense data, doesn’t work so well with modern physics that does go farther. It may be that there is an infinite line or protocol of nominal essences that one may go through with investigation to deeper, new understanding of the construction of quanta, fields, space and time.
Sartre pointed out that only God could have the point of view of the other at the same time as one’s own. That relation may be instructive for comprehending the limit of observing nominal and real essences.