There are two related issues here: the viability of XL Center and the lifespan of Gampel Pavilion. At 30 years and counting, this is the time where arenas either go through a major renovation of sorts (e.g., Villanova) or are planned for obsolescence and replacement (e.g., Baylor's Farrell Center, a 10,000 seat arena with much the same architecture as Gampel). "Major" renovations could include new electrical, plumbing, infrastructure, etc. and not just the roof.
The athletic department also knows the state isn't funding two projects. Back in the day, the University of Alabama played most of its big football games at Legion Field in Birmingham, and not on campus at Bryant-Denny Stadium. After numerous expansions, Alabama came to the conclusion that it made more sense to play on campus than in a decaying Birmingham, and while there was much loyalty around the old stadium, the fan base learned to travel to Tuscaloosa going forward.
So...does the state place a $800 million bet on a new XL/Civic Center without an NBA/NHL anchor tenant, or a $200 million refurb of Gampel to set it up for the next generation?