Per the interview they are making it sound like there is a huge discrepancy between USA and Canadian salaries for RN's. There is not.
Median RN salary in Canada = $83,200/year or $40/hour based on a 40 hour work week.
https://www.jobbank.gc.ca/marketreport/wages-occupation/993/ca
Median RN salary in the USA = $82,800/year.
https://www.incrediblehealth.com/blog/the-highest-paying-states-for-nurses/
Also, if a nurse wanted to relocate to the USA it is not as simple as moving down the street. There are a lot of costs, time and paperwork required to obtain a working VISA.
Covid has forced a lot of boomers to rethink how they want to spend the rest of their lives and many nurses are leaving the workforce. This is not uncommon to nursing as every other profession is going through the same changes.
This "talent shortage" is also not isolated to Canada as they are experiencing the same thing in the USA. The firm I work for is based out of the USA and we have hired dozens of Canadian people who work from home and report to and directly on USA programs.