Everyone speculating points out what has been said here many times....
Namely....as far as we know today, the franchise in its present location loses enough money every year that whoever owns it for awhile gets to the place where they don't want to own it any more. (There are many reasons for this, and some are historical and can only be blamed on, for example, the way that a lease with Minneapolis fell through when the Jets were leaving Winnipeg.)
There is ample reason to believe that, in the big-picture sense, the NHL itself is still calling the shots (For example, when Glendale cancelled the lease, or threatened to do so, it was reportedly the league which gave IA room to negotiate out of market - the league. Also, Bettman was quoted at that time as saying "We have an agreement with Glendale...." Note the use of 'we'. ) As I say, ample reason....NOT proof positive.
The many possible futures expressed here simply underscore the reality that if the first two paragraphs are true, then the NHL doesn't have a good answer for this situation.
Not having a good answer plays into Glendale's hands. Glendale right now has what they want: NHL hockey in their arena, at no extra cost to the city. As other options disappear, Glendale's hand gets stronger, not weaker. If Glendale hasn't negotiated a subsidy with the Yotes in the last few years, when there is potential competition for the team, it makes little sense that they would later, when the competition is less.
As far as how it harms the NHL right now: Having a team playing in the Phoenix market is not a problem. The crowds look better there than a few other places. So, for optics, relocating is NOT necessary. It's the financials which MAY be the problem (note the use of 'MAY').
If the losses become untenable, then what? Again, there is no good answer. The best financial answer, if it is determined one is necessary, is Houston. If Fertitta doesn't want to pay the price, then the best financial answer is Quebec. But, for other reasons, the NHL doesn't want to do that.
So, in the end, the franchise may stay right where it is, losing money which the BOG is responsible for, for a long time.