Truth hurts I guess. If the first 2 times it fails, try, try again
As has been covered before, the market didn't fail the teams, the owners failed both market and teams.
The Flames left because their owner, Tom Cousins, encountered financial difficulty in the late-1970s due to a collapsing real estate market -- something he was heavily invested in. He sold the Flames to the highest bidder, which happened to be an ownership in Calgary for US$26 million, a record for the time. To give you an idea how bad the real estate market really was, some of the players couldn't sell their homes, and used them as summer homes. Some players even retired and moved into those homes here full-time.
The Thrashers left because the owners literally didn't want the team. All of this was detailed throughout this thread, but you don't have to take my word for it, look up the court case of King & Spalding vs. Atlanta Spirit. Some of the details in that case is pretty mundane, but you'll find where Atlanta Spirit attempted to sell the team to out-of-market buyers in 2005. If Atlanta Spirit wanted to own the arena and the Hawks, they had to buy the Thrashers, or they'd get nothing. The fact that AOL Time Warner sold to Atlanta Spirit resulted in a different lawsuit, McDavid vs Time Warner.
It's fun to post one-liners based on nothing except what you want to believe, or what others would have you believe instead of the truth. I read political Twitter threads, and I know that type of post well. It's another thing entirely to actually do a little research. I know, research isn't always fun, and it might actually cause one to change their positions on things, but you'd be far better for it.