You can call BS as much as you want, doesn't make it true. Us leaving the reality of the industry should know better, when we are ACTUALLY LOOKING FOR JOBS.
But by all means, do your own research: open Indeed, LinkedIn and the Careers pages of all of these and see how many job postings they have for Calgary and how many for Edmonton, especially for corporate jobs (we're talking about high-paying finance, not branch receptionist or cashier, here, after all).
And the same goes for all other banks. Not to mention how many Capital Advisory, Investment Banks, Portfolio Management, Auditing and Accounting, Management Consultants, Business Consultants, etc they have, whereas you can probably list all of Edmonton's in your hands. And this is simply because instead of attracting head offices, we became an almost strictly industrial centre. It's not rocket science.