Interesting...spent 20s in city also but now live in suburbs and don't feel isolated at all. We know all our neighbors, our kids play together etc. I didn't know any of these people before we lived there obviously.

Would argue it's less about "where you are" and more about "how easy it is for you to make new friends" but that's purely anecdotal.

I guess if it's about going to bars to make friendships then yes there will be less of that in suburbs (assuming U.S. here). But as you age going to bars is a "need" that seems to generally decrease for most (not all of course) people.

How is a suburb inherently lonely exactly?