After buying and playing this game since February, I noticed that there are always quite a few server that ban the use of the Mortar (Truck), the SMG08, ands occassionally the Heavy Bomber. It seems like these are more or less commonly accepted restrictions, as they are often seen as ruining other players' fun or simply being unbalanced.
What I can't understand for the life of me though, is how I have yet to see a single server banning the use of the M1917 Telescopic variant specifically. Sure the SMG08 is 100% a sweat gun, but then the M1917 Tele is for morbidly obese sweats that can't even move, and would IRL break a sweat on their toilet break.