Yes, that assumption is called the Ergodic Hypothesis, and generally justified in undergraduate statistical mechanics courses by proving and appealing to Liouville's theorem.
It's worth noting that there's more than just ergodicity at play, although that's a fundamental requirement. For instance, applying the Pauli Exclusion Principle gives rise to Fermi-Dirac statistics.
Isn't that more about enumerating the microstates? The Pauli exclusion principle just ends up forbidding some of the microstates (forbidding a significant fraction of them if you're in the low-temperature regime).
vitus|10 months ago
tomnicholas1|10 months ago