IMO the pedestrian infrastructure and presence of things to walk to matters far more. There's a 4 lane road in my city that goes by the university area and it's fine because that area was designed with walking in mind. The area is full of high rise apartments, countless restaurants, a world class university, a massive park, and has a nearby LRT. There's even a pedestrian overpass.

Speaking of overpasses, I noticed really great underpasses when I visited Warsaw. They had some really large streets, but they weren't an issue cause you could just go under the street (and that was also filled with shops). I found Warsaw to be a very walkable city and it was largely because of stuff like underpasses and simply things of interest being close by.

I had a similar experience visiting London but because of the Tube. London's public transit is literally the best I've personally used. Despite being a foreigner, I was able to get to literally everywhere I wanted to go with ease. I only wish Canadian cities would emulate that instead of the States as they tend to do.