I think the word “freely” is doing a lot of work here. How free? Crowchild is free-flow about a block away. All of Calgary's main streets feature cars, many/most nice retail and shopping streets in Toronto and Montreal also allow cars. What is less common in Montreal and Toronto is how often the car commuter is prioritized over local needs in these shopping districts. Calgary does this all the time.
This is too binary - it's not all or nothing. What it should be is a legitimate sliding scale, where in shopping districts and main streets pedestrians and local businesses are actually prioritized over commuter traffic.
This doesn't mean "ban cars", it means if the trade-off is between a wide curve to allow for cars to turn at speed and a narrow curve to slow cars and give more space for pedestrians, do that. It means allowing crossing pedestrians to go first and avoid advanced-left turns that delay pedestrians. It means lanes can be narrowed to give more room to sidewalks, even if this means cars will have to be a bit slower. That kind of thing.
Here's a few 34th Ave equivalents in Toronto. The all are just off of a "main street" in the way Calgary thinks about them, but they themselves don't connect much to the larger grid, just like 34th. Notice the cars are allowed, but the need to commute is really not the focus - narrow, one-way, low curbs, stop signs. Nothing is designed for speed here and that's okay, it's not important. That's what the Crowchild Trail's of the world are for.
Baldwin Street (near U or T):
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Yorkville
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