> Something I don't see mentioned often in this discussion: what's a "long distance". Is there a formal measure or comprehensive view on that question?
It may partly be psychological: in 'the city' there is human activity and you do not feel isolated, and you feel part of societal activity.
> I also live in what feels like a dense suburb. Many houses close to each other. Example: https://maps.app.goo.gl/KBcvG5vnnh48hGwY8
LOL: have you noticed the lack of sidewalks? Here are some examples of what is a "streetcar suburb", which was developed in the 1890s/1900s:
* https://www.google.com/maps/place/50+Geoffrey+St,+Toronto,+O...
* https://www.google.com/maps/place/150+Geoffrey+St,+Toronto,+...
* https://en.wikipedia.org/wiki/Streetcar_suburb
* https://en.wikipedia.org/wiki/Streetcar_suburb#Toronto
* https://en.wikipedia.org/wiki/Roncesvalles,_Toronto
A good portion of these houses were built before the car was invented, and while many folks park on the street (you have to pay for a permit), there are also lanes and garages for many of them. A couple of schools with-in walking distance, banks, churches, library, shops, etc.
Sidewalks are missing there but there are plenty in town.
I used to live in two of the streetcar suburbs: Newton Ma, and Brookline Ma. They are indeed more urban than suburban in many spots, but again, proximity matters. Those places feel more urban when you live near the MBTA Green Line (the streetcar) - let's say within 10 min walk.