I also grew up in the suburbs in the 1980s, both in Florida (more rural northwest) and Illinois (Chicago suburbs). The suburbs of my youth don't exist anymore; certainly not the ones I actually lived in. The streets are far more dangerous because cars drive faster and they seem to be more reckless (e.g. idiot kids or grumpy adults racing down the block in cars that outperform sport cars from 20 years prior). I used to regularly walk 2 miles to high school (when I slept late and missed the bus), a portion of which required walking on the side of a main thoroughfare without a sidewalk. Cars today drive 50mph or 60mph on that road whereas they once drove 30mph. I wouldn't walk that route as an adult today, and sure as heck wouldn't let a kid walk it regularly.
They do exist in some places. I've seen them and have visited friends living there. Cul de sacs in subdivisions still on the city periphery, predominately Mormon neighborhoods in Utah where people expect kids to dart into the street, or tony gated communities. But they're just not as common. And in any event, even when they can, kids these days don't spend much time outdoors. In places where I did (and kids still can) spend all day roaming around in the woods or riding their bikes across town, today's kids spend all day playing video games or chatting online. Even if I my kid chose to hang outside, he'd be playing alone much of the time.
As someone else mentioned on HN a couple of years ago, you can optimize for a kids ability to play in the streets when he's < 10 years old. Or you can optimize for a 10+ year old to have the freedom to get around an entire city by himself. These days you can't have both, unfortunately, whereas once upon a time the city offered both (when kids could play in the street because drivers and cars were less threatening).
Times are different. I don't dislike the suburbs, I just don't think they're sustainable. Most often suburbs deteriorate quickly within a decade or two. The qualities that make them livable disappear once they're subsumed by a new ring of suburbs, bringing increased cross traffic and a new generation of childless homeowners.