Dropping the tower also spawns the attack boat, which is the best anti air in the game. Zero advantage for choppers to drop it imo.
Spoken by someone with no skill in a heli.
Tower up, tower down, makes very little difference. Few players in the boat are good enough to warrant any amount of concern. Arguably, dropping the tower helps the helicopter rather than hinders it.
If it's a good heli, the gunner's running thermal anyway, and most commonly the good pilots run Spray Snow camo which blends into the dust like you would not fucking believe.
In hardcore it's even funnier because on the ground: Good luck spotting the heli before it spots you, good luck doing damage to it, and even if you do damage it, good luck convincing your team to capitalize on it, and even better luck trying to convey where the heli is at in the moment because, your ass is dead and your last known position for that heli may be half a map away by the time your slow ass can type it out in chat.
The only disadvanatage to an AH team in dropping C is the pilot loses visibility in the dust, which a good heli team the gunner will be calling things out to the pilot anyway which renders that null.
C on Siege is the tallest building in the map and I love when dumb fucks drop that tower because it removes the parachute-to-every-fucking-roof solution and gets dumb fucks off that roof, which means far less stinger coverage and far more angles to object & terrain mask said stingers with.
I love it when stupid retards take the boat to their spawn because that means me and the pilot go in after the boat and anybody dumb enough to shoot at us while we deal with the boat gets facefucked alongside the boat in the process because they're no longer protected by the uncap rape whistle rules.
By all means, drop C or don't. I have a preference for dumb shits who drop C, obviously, but it's 49/51%.
Doesn't really matter, you're still there to get farmed.