The true rooftop pools I have seen in Charlotte in apartment or hotel towers are more akin to super sized rectangular hot tubs without the jets. They are usually very shallow. Actually this proposed pool deck atop probably the parking garage as someone mention looks great. It is still elevated and it is the top of the roof that wing of the building.
This is the typical Miami model where the recreation deck is atop the pedestal parking deck. It’s a bit lipstick on the pig, but it’s better than a pig without the lipstick.
To a large degree the pool on top of a parking deck is a structural decision. Pools are heavy and decks can be constructed to support very large dead loads. Plus no pool size or depth constraints and plenty of sunny deck options for the surrounds.
Putting a pool on a building rooftop, like Skyhouse, limits both its depth and size. Plus there’s always a leak concern even if just tenant imaginations.
Personally I wish all parking deck top levels, whether public or private, were required to be open space improved with park amenities (dog parks, green space, etc). No one wants to park there anyway and they are a blight on the accompanying tower’s viewshed foreground.