Cycle tracks are about complete streets: help calm traffic and create streets that include everyone
On first view cycle tracks (separated bike lanes) seem to be just about cyclists, but in New York and elsewhere it's been found to provide great benefits to pedestrians and to street life. They help create islands of refuge for pedestrians crossing wide roads; they provide a barrier between pedestrians and car traffic and they get all ages, young and old onto bikes and other mobility devices (like wheelchairs).
For Toronto, the proposal to build cycle tracks downtown would help provide this well-rounded benefit. From NOW:
“Many cities are implementing this type of separated infrastructure, and they’re seeing really great result in terms of safety for all road users,” says Andrea Garcia, director of advocacy and operations at TCU. “It creates these low-stress bikeways that encourage folks who are on the fence about cycling to pick up a bike and start using it. It’s not the first time [separated bike lanes] have been proposed, but it’s the first time they’ve really been championed in this way.”