don't really see a problem with their guncom besides having a beyond broken chrono, shield is nice to be offensive and works great if you want to be volatile on the ground, kiting isn't too bad and it comes with a huge tax in a form of apm, mid and late game also comes down to gc being ignored for no reason whatsoever for 1 year by now.
can't see aeon guncom broken late game as well and i'd call it pretty garbage considering that:
1)uef has BaD bIlly NuKe that will surely not whipe a 10k investment randomly
2)sera has a small 50k hp buff and pretty good double gun to play vs land and some exps
3)cyb is just garbage but still gets access to cloak+lazer that can be brutal
aeon has +4 range, cool. (no chrono involved or banned from lobbies)
anything smaller than 3v3 can probably be facing the unstoppable aeon gun com but it's more of a powerspike that you should be at least trying to counter, it's also a combination of aeon having probably the most cost-efficient land in the meta that is also contributing to indirect guncom buff since it gives you access to cheap mobile shields