You could have gotten a very nice customer service rep. Or they saw your status whilst rebooking you and gave you a pass. Or perhaps doing it in person at the airport helped your case.

I don't doubt your positive experience. What I do doubt is "they would do it for anyone".

I had a YYZ-JFK-HND in AC J/ANA F in February (award ticket), with a 14.5 hour layover at JFK. YYZ-JFK was operated by AC - cancelled 9 hours before departure (1200 for a 2055 departure). After much insistence on my part, the CSR (phone) ended up rebooking me on the final YYZ-LGA of the night and I self connected to JFK.

I suggested more than once to be rebooked on Delta or American (the only other two realistic airlines I would have picked who operate this route. Flair was an option, but...), for both the evening (there was only one other Delta flight) and the following morning (2 flights that depart before 8am to JFK) when the rep was searching for alternates. The rep insisted "Air Canada will not book you on a competitor's airline". Mind you, I called the priority line.

If I had to guess - the success rate of being rebooked by AC on a competitor's airline/interline partner/etc., is extremely low.

And if I had to guess, status can (and likely does help) when it comes to IRROPS and a bit of flexibility. Or HUCA (if you don't mind the hour long wait times).

Sure, APPR (and generally speaking, most air passenger rights) say airlines are supposed to rebook you even with a competitor if necessary. But what are you going to do when they don't? Complain in small claims a year after the fact?

Sucks for those travelling in September, but I would say for those people - good luck, you'll probably be spanked by AC when it comes to rebooking and compensation. I wish I could give AC benefit of the doubt.