Well, to correct you, you are wrong.
Silencers when properly constructed have a HUGE benefit. Ask to see Ganef's OPS silencer or, I could show you my Head 19.50 silencer at the next game. They make a huge difference in both the octave and report of an AEG, again, when properly constructed.
A low-noise grip plate is said to help also, since most of the noise produced by the firing process comes from the grip's motor compartment.