What anthropic do you mean? I'm describing properties of models, not people. Physics (probably) doesn't care what you "know".

On the guid idea - fundamental particles are indistinguishable from one another in quantum mechanics, so they don't have anything like a guid even in principle. There is no experiment you could perform on an electron to determine whether it had been swapped out for a "different" one, for instance.

Maybe I'm missing your point though?