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Ace Combat does this too—although in that case it's less "lacking the equipment" and more "there's no way real-world militaries would be using the same unencrypted radio frequencies so that everything anyone says is heard by everyone else—not to mention you also somehow pick up civilian news broadcasts and police radios".
Ace Combat: Assault Horizon lampshades it when the enemy Ace Pilot starts talking, your wingman tells him to get the hell off this frequency, and the enemy replies that "Your encryption protocols are terrible," implying that the communication is encrypted, but he cracked it. Every other game plays it completely straight without mentioning it, though.
Edit: I checked with some other tropers and this would be a Sub-Trope of Enemy Chatter, but I do definitely think it's worth a Sub-Trope depending on the number of examples. Enemy Chatter is just dialogue between enemies, and doesn't require any radio equipment, which means it's generally pretty reasonable. I think this is more than distinct enough for a Sub-Trope, since it relies on the unspoken idea that everyone has a radio tuned to the exact same frequency, and it's not encrypted or protected in any way. Which, in many cases, is completely absurd.
Edited by SolipSchismHollywood CB is about unrealistic use of radio communications, yes, but the article at least specifies that all speakers have radios to begin with. This is about the player character in videogames being able to pick up radio messages without even having a radio. There is overlap, but it's not quite the same.
^^ Sorry, I came across Hollywood CB in my search but neglected to mention it. Hollywood CB is about a specific type of unrealistic CB radios in which they function like telephones. Related, but distinct.
Edited by SolipSchism

Is there a trope for when the player character is able to pick up on radio messages (Usually but not exclusively Enemy Chatter along the lines of S/He's here!/We need backup!), without actually having the required equipment to intercept such messages? It's ubiquitous in GTA, Crysis, Borderlands, and a bunch of other series I can't remember right now.