It seems like Cybran carriers have AA that is REALLY terrible at hitting things.
In the game I just did I made 12 of them and even that amount cannot kill a single T3 transport because most of the shots miss. At first I thought this might be because the transports are carrying XPs which is unusual or some other map related reason. However I did a game with cheating on in which I found that all other carriers have no problems hitting these transports and that the Cybran one also miss regular gunships.
https://youtu.be/n3BGt7CrTiM?t=2150
I suspect this is a bug. Surely these carriers are not supposed to be this bad? They can't even hit targets flying in a straight line at a constant speed!