It's certainly overused in the game, but it's not overpowered. It just covers turf arguably the best in the game, but that's really all it can do. People saying its OP clearly don't realize its easy to just out range one. Just some advice, I would avoid bringing it to ranked as you climb up the ranks, as people will be using weapons that will easily beat the Aerospray.
Yeah- I'm getting tired of seeing Aerospray MGs left and right, but they're honestly not too hard to beat.
Curling Bomb Rushes, compared to other forms of Bomb Rushes, are actually kind of easy to avoid, plus I've managed to splat the Aerospray user plenty of times, while they were in the middle of a BM.
The Aerospray MG from the first game was better suited toward Ranked, I think: the Seekers made it very viable for stages like Walleye Warehouse and Port Mackerel. The AMG's sub was what I mainly focused on, as a weapon and means of travel.
Also, the Inkzooka was an excellent special for the AMG, what with the weapon's very short range. Perfect for taking out snipers.
I'm honestly surprised the MG wasn't as popular in Ranked in the first game- on good days, I could splat 10-15 people.