I would rather see GTA or Hamilton over Atlanta. New York and LA easily support two teams. I think GTA could too.
GTA and Hamilton have barriers that Atlanta doesn't: The Leafs (and Sabres). That significant barrier would've been a whole lot easier to overcome in the 80s or 90s, but at that time, the league didn't want Hamilton either. Whether or not a GTA team would work is a question I can't answer.
32 is literally the perfect number of teams.
I'm old enough to remember reading people say the same about 21. Whether 21 was or 32 is or isn't is a matter of opinion, not fact. At this point, it sounds like the league disagrees with everyone making this argument.
Atlanta is a different story for me though. While I am aware that the Atlanta Spirit effectively did everything they could to get rid of the team, I don't recall the team being a success off the ice prior to the Spirit Group either.
No... the Thrashers were never really a success in its entire time here. If you're going to have a team in an area no one wants to go, the team has to be worth the price of admission. That lack of success and poor choice to put them downtown was already two strikes against them.
The NHL is the least popular and money-earning league of the Big 4 and yet they'll have the most teams. How does that make sense?
This particular argument is indicative of an entirely different problem: Marketing. Even today, the league depends on teams doing all the legwork when it comes to marketing its stars, while other leagues seem to have little problem marketing theirs.