Bingo
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There are different theories about it. One i encountered which seemed well researched determined that the first instance was a rap song referencing a local police code for a particular crime.
(Basically like your 187 which appeared often in 90s west coast gangster rap and referring to redrum on a police officer in the line of duty)
From what I can tell from my 12 year old daughter it is mainly a game of "we are in on the joke and you arent" sort of retarded thing where any time those 2 numbers are mentioned kids giggle and repeat it like idiots because they are kids and kids are idiots and I am pretty confident the vast majority of them don't even know what it is supposed to mean they just play the behavior out by way of imitation and a modern day social media algorhythm sort of brainwashing.
Somewhat akin to the Emporers New Clothes" phenomenon in which people play along out of fear of being left out so they all pretend the same dumb shit together to fit in the the crowd rather than swim upstream/ go against the grain.
My 13 year old daughter who is MUCH more independent and doesn't really give a fuck about trying to impress her peers rolls her eyes at it more than I do.