At 1:26:28/2:56:12 in A Bridge Too Far, Maj Gen Urquhart and his squad or platoon (I'm uncertain which term) are behind enemy lines and trying to dodge Germans. But why didn't they silence or suppress their weapons? Doubtless they wouldn't desire Germans to hear gunshots that'll just attract more Germans to Urquhart's hide-out.
Silenced pistols DID exist during World War II. Silencers were regularly used by agents of the United States Office of Strategic Services, who favored the newly designed High Standard HDM . 22 LR pistol during World War II. They just weren't widespread devices. also alot of pistol ammo in those days were subsonic, thus noise wasn't much of a major issue.
Silencers and suppressors weren't all that effective in World War II compared to now. They also reduce muzzle velocity, which means they reduce accuracy and range, and they have a limited durability.
As such they weren't general issue - some commando and other special forces did receive suppressed carbines - but during the war, Allied paratroopers were not kitted out all that differently to regular infantry.