Of course the kids need to go outside to meet those other kids (and the other kids need to go out as well), and parents need to let kids out of their sight to go to the park.
These low-density car-dependent suburbs provide a very poor experience for everybody outside a car, from children/teens who can't drive yet to people who are trying to get to a destination (work, shop, library, restaurant, etc.) without a car.
Is there? This is actually a problem. In many neighborhoods, especially in the nicest areas where people are richer, there are fewer and fewer kids. Today, there are significantly fewer kids than adults. Just a few decades ago, kids outnumbered adults in many neighborhoods.
I mean this really matters. If you have a community of 40 families and twenty kids, there's hardly any kids that can actually play with each other. They're probably too different in age, to have groups of more than 2 or 3, and that's a stretch because if you only have two or three there's a significant chance you may not get along / might not be super-interested.
Why not? Mine sure did.
Sounds like Toronto suffers from L.A.'s problem: It's an asinine mess where you're going town a street and then... it dead-ends into a house. It's irritating as shit. None of the streets go anywhere.
Until you actually try to go anywhere and find that you cant't without riding through an arterial road with heavy dangerous traffic. The quiet suburban roads don't form a network that allows you to go to actual destinations.
Here in Toronto they are trying to address that by building (a few) cycle tracks running parallel to these horrible arterial roads, but it's still an awful experience. There are a few quiet greenways without any motor traffic, but they don't help you reach any destination.
Neighborhoods that were built before the advent of the car are more amenable to cycling.