I'd rather face 88's firing at me, cause I can see the tracer coming up.
It would seem the OP would or should be just as irritated at the 5' fire from the fleets..........those things don't show a tracer unless they are in HE mode, and they don't have to be continually fused by the operator like the 88's do. And they fire in batteries of two guns, doubling the odds of getting you.
Either way, I do man the 88's from time to time, usually when it's too late to up a fighter to intercept buffs, or there is clearly a horde inbound and all you are gonna by upping a fighter is sacrifice yourself to pad someone's score sheet.
Do I fire at fighters around a base I am defending? Sure I do. Usually I limit that to when I see 2 or 3 or 4 fighters ganging up on a friendly. If that makes folks upset, too bad. I don't participate in the activity when I see several friendlies swarming an enemy, so if someone throwing a few flak bursts out there to make the gangers nervous, and maybe even damage one of them, I will do it.
Some folks will say that behavior is normal when you are trying to take a base, any means necessary is acceptable to achieve the goal. But someone lobbing AA shells in their midst is just as acceptable in my eyes.
In the end, it's just a game.