[umbra07]

It seems sort of like calling other people ma'am and sir in America. Everyone knows what those words mean, but younger people will almost never use them (except in specific American subcultures). Some people may be offended if you call them sir/ma'am.

[encom]

The YouTube algorithm has seen fit to serve me a bunch of American police bodycam videos lately. I find it super bizarre that a policeman will address everyone as sir. Including some deranged crackhead, without pants, charging at him with a sword. Decidedly not a "sir".

In Denmark nobody adresses each other formally, unless you're royalty. Parliament also does it during debates, but that's pretty much it. It's weird when it happens, and it's usually some store clerk that does it out of a misguided attempt at politeness, but to me at least it has the opposite effect. I am not a Hr. (sir), I'm just some dickhead buying cigarettes at 1 AM.

I Denmark we at least pretend everyone is equal. The CEO of the company is just John. We eat lunch in the same break room at the same time.

[jfinnery]

The way US cops talk is a whole thing. It’s one of the most-distinctive job-related American English variants. Even more so than white-collar “business English” (“let’s take this offline and circle back to it, as per my prior email”)

Some of it’s weird posturing (I’d put the “sir” thing in that category) and a bunch of it’s a combination of actually-effective and folk-supposed-effective ways of speaking to dazzle jurors, plus probably some other motivations and influences thrown in (some Hollywood-military turns of phrase and vocabulary, certainly)

[anthk]

In Spanish the Police/Civil Guard (militarized police) does the same, they will address you like "Disculpe, caballero" - excuse me, (Gentle) Sir. They will address you very formaly, and you might shit bricks on the road in case you messed up something or have a faulty light.

[DiggyJohnson]

US English doesn’t really have an informal version of “sir” for the situation you described. Closest would be “hey” or “yo” etc. but those aren’t even (pro)nouns.

[stirfish]

Sounds like a duel with a knight, so "sir" feels appropriate.

More seriously, I think it's possible that "sir" can be used in a way that casts everyone as equals. Like, you can be in a crackhead's den and recognize that he is in important person in that environment.