TNT belt is the equivalent of the old WCW TV title. Gets defended a lot on TV. Should be every week, I agree with that. I think the WCW belt had a "defend every week" rule.
All-Atlantic belt is the equivalent of the WWF IC title except it's actually "intercontinental" for real, can be defended in other promotions in other countries. Wouldn't be surprised if the idea here is to have it be defended a lot in New Japan, or held by NJPW guys sometimes. The reverse mirror of the NJPW US title in that regard.
FTW belt is a Ricky Starks vanity belt, nothing more. It's been held by a grand total of two guys in AEW. Not too sure what the point of it is, but it's a vanity belt.
ROH belts are all only on AEW TV until ROH gets a new TV deal, then I'm pretty sure they're all heading over to that show.
TLDR every belt on their show has a purpose, and there's still room for Trios belts. The only title I don't like in AEW is probably the TBS title since it felt so...unnecessary. Plus Jade is completely upstaging Rosa, so right now it feels like the TBS title is the main women's title. Might as well just have Jade defeat Rosa and merge the belts at this point.