It takes a lot of the magic out of it. I’m sure a bit of this is rose-colored glasses, but it was a really neat experience as a kid. The entire neighborhood was out in the streets, people got to know their neighbors, and you felt like you were part of something. These days, it feels spooky due to how empty it is besides cars.
There are some municipalities where landowners are required to remove graffiti in a timely fashion or be fined by the city. In such places, the landlord would definitely pass those costs to tenants. Not that they would lower rents if the problem went away, of course. One year of a graffiti problem would likely permanently raise rents unless you live somewhere with a glut of available affordable rentals.