CSAT Uniforms have an armour layer under their BDU, you can see part of it on their forearm region, whether you think that's realistic or not is irrelevant, that's the setting. Thus it's not a bug.

And you should refrain from implying someone is mentally ill or "a kid with down syndrome" simply for answering your question, it's a great way to get banned.

Snipedhunter, you realize that Hollywood action movies and typical first person shooters (which take a huge amount of their visual and sound design from action movies) are a really crappy reference source right? Even a movie that's trying to be somewhat grounded is going to take liberties for dramatic effect or to communicate something to the audience. Every bullet producing a dramatic whoosh regardless of range is one of those liberties.

At normal fighting ranges the sound of the bullet moving through is far exceeded in volume by the supersonic crack of the bullet. The only exceptions to the rule are naturally slow and heavy rounds such as the .45, subsonic ammunition with reduced powder loads designed for use with a suppressor, or supersonic rounds that have traveled far enough to go below the speed of sound.

Most of the disadvantages of running a suppressor on a weapon are related to wear on the weapon and overheating, Arma 3 currently has no built in simulation of overheating. In real life firing a weapon with "hot" ammo out of a suppressed weapon will indeed slightly increase muzzle velocity, but its still going to be very loud. At best you're going from "gunshot" to "car backfiring"

Originally attaching a suppressor would magically make your gun act like it was loaded with subsonic rounds, which is what actually provides the decrease in damage and range video games associate with Suppressed weapons. This was removed because it was dumb for your ammo to magically change powder loading.

But it was only half done, so right now you have a situation where the ballistics of firing a hot load out of a suppressed weapon are done right, but the sound simulation isn't. But the problem is that if you do the sound simulation right, you're going to get a bunch of people either complaining because their suppressor "isn't working" or complaining because Subsonic rounds have crappy ballistic performance.