In my Brooklyn neighborhood the density feels fairly low (10-15 visible in the street). Green space isn't great for most but I happen to live two blocks from a park.
Many places in Manhattan also feel like this if they aren't business or nightlife heavy.
Interestingly, Chiyoda, the Tokyo ward in which the street view you provided is located, has the lowest population (by which I mean the `resident' population density) among all wards in central Tokyo[1]. I believe that this strongly supports your point that the `suffocating' parts of a city does not really have many people living there.
[1]: https://en.wikipedia.org/wiki/Special_wards_of_Tokyo#List_of...
And yet the most densely populated districts don't feel all that bad for the most part. Kwun Tong https://www.google.com.hk/maps/@22.3138909,114.2268051,3a,60... and Wong Tai Sin https://www.google.com.hk/maps/@22.3435765,114.1929784,3a,75... for example. But Mong Kok is a subdistrict in Yau Tsim Mong, famous for being the most densely populated place in the world.. AND it's a shopping district too, with huge influx after working hours. https://www.google.com.hk/maps/@22.319367,114.1699535,3a,75y...
I strongly suspect when people say that, they're thinking of the day time population of the tourist/business districts in those cities. The daytime population of Manhattan is nearly 4 million people, mostly concentrated below 130th street. The density is probably 200k-250k people per square mile. The resident population density is actually only 70,000 people per square mile. I was there after Hurricane Sandy, when the commuters and tourists were gone, and it was empty.
Here is a typical side street in Rogers Park Chicago: https://www.google.com/maps/@42.0103744,-87.6640436,3a,75y,2.... At 30,000 people per square mile, it's about double the average density of Tokyo.
Here's one of the newer business districts in Tokyo: https://www.google.com/maps/@35.6807167,139.7630674,3a,75y,9.... That area probably has way above the average population density of the city.