People talk shit about the flight controls in GTA, but I kind of like them. They're just close enough to sim-y that you can't just go flying around in them the way you can in cars, which makes all those hours I spent Pilotwings on the SNES seem like an actual skill as opposed to just an excuse to listen to sweet mellow Japanese grooves
In a lot of games "flying" just feels like zero gravity hovering, with no momentum or sense of relative speed
Pit will react to how fast he's flying, even to go as far to yell about how much g-force is pushing against him, albeit it in a comedic tone. Soaring past the scenery with plenty of sound effects, scenic views, and dodging in between caverns or under cliffs really gives the feeling of soaring. As a fan of the 3D mechanic in this game, that just adds more to it because of the depth, like you can see just how high up you are.