There's something really beautiful about streets without setbacks like this [1]. I can't put my finger on what it is but they're all over Amsterdam and Japan, and they always make me so happy to walk though. Does anyone know what it is about these?
More seriously, my guess is that you enjoy those streets because there's so much more character to them. They are generally part of an older, more storied urban core, so the streets are more imbued with a "there"ness of the community.
Contrast this with the experience of walking down a recently-gentrified street.
Human scale, as noted. High variety. A ready change of scene or situation. Opportunities located in close proximity. And generally, an active (and frequently well-behaved) street life.
That said: I'd really like to see a list of places which afford such environments.
I think part of it is the visual complexity. Uniform color and shapes of a normal street is boring. Easy access to both sides of the street is also appealing. If the woman to the right wanted to go to the ristorante on the left she could be there in seconds.
I can't stand them myself; they're rarely that uncrowded and many streets with cars/cycle traffic here also don't have setbacks while, at the same time, allowing private property to build high walls.
This results in a large number of blind turns where you can't tell if anyone's coming around the corner unless there are mirrors available, which aren't always a guarantee.
It is human scale rather than car scale. Things being closer together makes things more enjoyable for humans. For cars, we go so fast past things, we want them farther apart to perceive the same amount of changes. Car scale makes us think we should spread stuff out more.
Lack of cars and the fact that you're near other people. We are social creatures, we need some minimum amount of space, but more than that just makes us feel isolated.
[1] https://pbs.twimg.com/media/ELaN6w_UUAAQbOC?format=jpg&name=...