Yes, I believe that external environment is a very big factor. I lived in major cities including Istanbul, NYC and LA and I know that it is not for me.
I am miserable in big places with bunch of people on top of each other; horns, traffic, speed, expenses, competition...My anxiety was worse, I was eating purely, not exercising and needless to say, I was annoyed with breathing dirty city air.
I love where I live now. It is very quite, life is very slow and people are just laid back and chilling. Nature is amazing and healing. I didn’t have any of this while living in cities.
In fact, i have to drive into the city twice a week and I hate it. It is a lot on my nerves.