Florida let the players go for cap reasons, yes. There is an unofficial internal cap of $75 million, which is more than enough to field a competitive team. As the league salary cap rises, you are going to see more and more teams having internal caps so that they aren't bleeding money.
But I don't see the comparison to Arizona. For years, Arizona has struggled to stay above the cap floor and aren't doing much to make a competitive team. Florida has had some major missteps in management, which has soured the fans, but they are spending and working hard on building a strong team. It just hasn't worked out quite yet other than their strong season a couple years ago. Whereas Tampa has had sustained success for years, and the fans have showed up.
American markets in general are going to be more fickle than Canadian ones, but if you win consistently, the fans will come. The Coyotes should be focused on building a good team that wins year after year, and then the attendance will sort itself out.
But look at the graph in this link and tell me something. Is it better to have another Winnipeg-like franchise who is limited by a small building and small population or is it better to go after markets that are flush with populations and money to maintain a viable franchise in the area? This is the thinking behind the Vegas and Seattle expansions, and why Quebec isn't anywhere on the radar.
http://www.espn.com/nhl/attendance
Winnipeg attendance: 15321
Florida attendance: 13851
They aren't that far apart at a difference of 1470 fans on average, and that's because the Panthers were bad for the first half of the year.
The income is probably favorable to Florida once you convert those attendance figures into American dollars. In 2015/16 during their 100+ point season, the Panthers attendance was 15384, ahead of the Jets, which was also skewed due to fans not showing up for the first part of the season. The building was full throughout the last 1/2 to 1/3 of the season. That's what happens in America; if you don't win, the fans don't show up.
This doesn't take into account broadcasting deals or the arena deal that gives the Panthers extra income from non-sporting events and low rent/major tax breaks.
At the end of the day, this is all about economics, and South Florida is still a perfectly viable market, even after so many years of poor results. I'd be far more concerned about what's happening in Arizona, Carolina or even Long Island before I was concerned about Florida.