The article is confused. The opinion is, it's so much safer _now_ than it was in the 1970s, it makes no sense to restrict children's wanderings.

But the article doesn't consider whether restricting children's wanderings is the REASON it is so much safer for children now.

"We have so many fire-safety rules in the building codes in Seattle. But get this: we haven't had any major fires since 1889! It's obvious we don't need these rules!"

It's true there is a cost to restricting children. But let's be a bit more realistic about the tradeoffs.