https://www.decathlon.ca/en/store-locator

There are 16 decathlon locations in 4 provinces. They also have an online store. The Toronto suburbs stores closed. They by no means "basically left Canada". They just left the GTA.

Much to the surprise of many in Ontario, there are quite a few places outside of that province that can be considered Canada.

They are still in lots of cities outside Toronto.

Are you sure? I spoke about decathlon in Canada with a friend of mine living there (Ottawa) and she says it’s there.

They seem to have tried and given up in the US as well outside of an online presence. It's a pity, as they make 'ok' gear at good prices. It's perfect for if you're getting into a sport, or know you're going to use it only casually and don't want to spend a lot on high-end gear, but want to avoid getting something that's completely cheap junk.