This is just a side note.
In 2019, my wife and I lived exclusively outside Canada and had no immediate plans to return. I'm a citizen, and my wife just had a TRV she used whenever we would visit the country. When entering Canada that year, we were asked to see an immigration officer at the airport. The officer asked why my wife didn't apply for permanent residency. We told him we didn't have immediate plans to move to Canada. He seemed slightly irked, and he reached and grabbed a thick reference book from a shelf behind him. It was the Immigration and Refugee Protection Act, in which he has many bookmarks. Without flipping through the book, he directly opened the page where he showed me that the wife of a Canadian citizen can apply for PR while the couple is living together abroad. He said that she can apply and acquire permanent residency, and even if you don't have plans to return to Canada, her PR can be renewed while we live together.
I know there is a requirement to outline plans for moving back to Canada, but what the officer said made me feel that as long as you hold a source of income wherever you are and you will provide proof that you will have enough funds to support you and your spouse when you move back to Canada, that will be enough. This is very similar to people who immigrate to Canada through Express Entry, for example. Express Entry candidates need proof of enough funds before they are given PRs. If that is the case with Express Entry candidates, then it should be at least the same for someone who is already a Citizen. I don't think they need a well-established source of income in Canada to be able to move back in with their non-Canadaian spouse.