It doesn't help that, as it's a dead horse, Baltimore has a horrible, horrible arena. One of the worst for any large city in the country.
Frankly, while "renovating" it sounds good, which is what is on the verge of happening, it's one of those cases where it's better to just build a brand new arena, in spite of the rising costs of new venues and the fact that the "benefits" of a new venue for the community are debatable. It's not a debate of replacing a 20-25 year old venue that still has a lot left in the tank; it's replacing a 60+ year old shithole that nobody outside of pro wrestling wants to do events in. It's a similar problem San Diego, Hartford, and every major city in Virginia are dealing with; they got crappy arenas that would be better off replaced entirely due to how archaic and unappealing they are for anyone, with renovations only serving as Band-Aids to the problem.
Obviously, getting the funds and dealing with the consequences of bending over to sports owners who want all of the rewards of a sparking, new venue but none of the responsibilities (maintenance fees, property taxes, construction costs) are major issues which means we shouldn't just build a new arena every time a rich person goes "I want one", but there are at least a handful of cases where building a new venue just makes much more sense.
The other issue is location. Baltimore is smack-dab between Philadelphia and Washington, which its often associated with in media markets. If you live in inner-city Baltimore, you probably would care for a minor league team, but if you live in the suburbs or general Maryland, you'd rather go to Philly or Washington D.C. to see the Flyers or Capitals instead of minor leaguers. It's a reason why the NBA or NHL would never work. Could a minor league team exist if a new arena ever is built, or if the Baltimore Arena renovations move it to the 1990s? Probably. But that team isn't going to live long.