I don't know what country you're in but in the US something like 80% of the population lives in urban areas where playing in the street is essentially impossible.

I live in the US. If you had been there and not just read some statistic you would have a better idea what you are talking about. The majority of the US live on quiet suburban streets. It is quite humorous how confused people get about America.

I don't know what "quiet suburban streets" you grew up on, but on mine the speed limit was 25 mph and people would zoom around at 35.

I've lived in the US my whole life other than 2 years in Belgium and 1 year in Afghanistan, I have a pretty good idea what I'm talking about.

The article is specifically about city streets, it even says so right in the article if you had bothered to read it.

um. http://en.wikipedia.org/wiki/Demographics_of_the_United_Stat...

It is very urbanized, with 81% residing in cities and suburbs as of 2014 (the worldwide urban rate is 54%)

Yes, suburban streets. Those are included in that 81%.

As of 2011, about 250 million Americans live in or around urban areas. That means more than three-quarters of the U.S. population shares just about three percent of the U.S. land area.[48]

we did this when we were kids, but mainly in cul-de-sacs.

And many suburbs are deliberately designed with tree-like roads, maximizing cul-de-sacs, and minimizing the probability of rat-running and other through-traffic.

Of course, without shortcuts and bike lanes, the same road pattern destroys walkability, because such road networks involve a trip to and from the trunk to get anywhere.

Then you have the gated communities of southern Florida, which are much worse.

Actually, China has gates, fences around everything, there is no such thing as an "open" campus or open apartment complex (unless it is very very urban). It is annoying to the say the least (especially when the gate you want to use is locked).