If this was a typical American suburb, I'd be inclined to agree, but you have to realize that your suburb is a statistical anomaly compared to the much more urban suburb that most Americans live in.

For most Americans, a suburb still means being miles from nature, it also means being jammed into row after row of houses butting shoulders with your neighbors. The "true suburb" (i.e., a suburb as it was originally envisioned) is a rare thing.

For these "urban 'burbs" there is really no benefit to the current layout of meandering streets and cul de sacs - it just forces people to drive more, disconnects neighborhoods, and makes transit impossible to provision. There would be very little lost converting these to neighborhoods with a stronger retail presence and sanely laid out streets.