Interesting observation, especially in light of the trope of the enlightened sage living in some mountaintop monastery somewhere.

I can tell you that theta neural oscillations are key to spiritual awakenings.

Taking your post as inspiration, I asked a search engine what high altitude living does to neural oscillation patterns. The AI component of the search engine pointed out that alpha and beta bands are reduced while theta band synchronization (increased power) can be observed, particularly during cognitive tasks, indicating increased effort to manage tasks in low-oxygen conditions.

I think the answer to your question is a resounding yes :)