I come from survivalist stock where my parents escaped smaller more rural places to make it in the city hence the opposite orientation.
There is nowhere on earth I am happier than at a family member's camp, deep in the woods away from everyone all by myself. Ultimately I think your last point is absolutely correct. I doubt I'd feel this way if this wasn't a lived experience while growing up.
When I told them about my dream home being a 500 sq ft apartment in the middle of a bustling metropolis, they said the first thought they had was “claustrophobia”.
But for me, small spaces in dense areas give me joy — living in the midst of an exciting morass of people where people collide in Brownian motion and new ideas form feel like happiness. This notion is much more common in denser places like Europe and Asia.
https://en.m.wiktionary.org/wiki/sonder#:~:text=(file)-,Verb...)
When I used to live in small towns, I would have a strong need to periodically visit a big city to restore my emotions. I love the feeling of being in a crowd even if I never talk to anyone. I love the bustle and noise and potential for new encounters.
Nature feels isolating to me. I wonder if I’m wired this way because I grew up in a big city. We’re wired to look for places where we can feel we’re “at home”, and that’s usually a function of childhood experiences.