To play devil's advocate, we need to stop and think why hockey in Atlanta failed multiple times.
The Flames flopped due to their inability to win (they never got past the first round of the playoffs), which caused them to struggle to endear themselves to people who were otherwise unfamiliar with the sport. The Thrashers not only faced the same problems the Flames did (inability to win) but later ran into hostile ownership that just didn't want them in the Phillips Arena, forcing the team to play in awkward dates and times that minimized potential revenue.
Meanwhile, back in the 1990s, the Atlanta Knights, an IHL team back when the IHL got bold and decided to take on the NHL, was outdrawing several NHL teams and even won the 1994 Turner Cup. And the present-day Atlanta Gladiators, despite being in Gwinnett County, are one of the higher-up ECHL teams in terms of attendance annually.
I'm not saying it can't be done, but things have to go right. And as things have to go right (you need to get a winner in almost immediately, plus have a venue that allows the team favorable dates), that's a nearly perfect storm of details that are almost too great to attempt.