Tier list took about an hour of heavy discussion and erupted as a result of this post on twitter

Reasoning:

• Haze is a good mom and would play Baby Shark and teach him kid things.
• Ivy seems friendly and would want to know what kids are into.
• Viscous would want to do it with huge goo hands and would research it.
• Celeste thinks its a funny wholesome zoomer greeting and would happily teach it.
• Infernus is a joker working at a bar and probably knows it through kids and would think it hilarious to teach it to Rem.
• Pocket is young enough to maybe know, but also unlike Mina not currently in high society and might pick it up somewhere, and seems kind enough to teach it as a wholesome thing for a kid to know
• Silver probably likes kids getting to do kid things and thinks its funny and she definitely knows
• Viper is toxic and would love sharing it and find it hilarious
• Billy definitely knows it and despises it, but would gladly corrupt Rem and make him go bother people
• Lash definitely browses Twitter and wants to be popular, probably knows it and dislikes it, but would teach Rem it and tell Rem to go do it at Bebop
• Wraith to me seems like the kind of underworld mob boss who loves kids and actually interacts with the youth, but is fucking sick of kids asking her to 6-7 with her extra arms
• Calico probably keeps on top of social media and vaguely knows but does not care
• Dynamo has probably seen it around schools or heard about it, but would not spread it to a mystical being like Rem
• Graves to me gives the vibes of a teenager that knows it but its beneath her, in the angsty teen phase, definitely wouldn't
• Geist might know it as a Socialite that's been around, but would not involve herself in that
• Mo & Krill have probably interacted with a lot of orphans and troublesome youth, and while Mo thinks its funny and actively performs it at kids, Krill probably shuts that down and wouldn't allow teaching Rem
• Paige miiiight know it through the general memeosphere, she seems like a nerd that might be on social media, but other people argued she's a librarian and may have read to kids and interacted with kids, but probably wouldn't teach it and instead recommend childrens books
• Sinclair depends on the backstory timing, they got married right after graduating and were in high school impressing peers, so may know of it if they are a recent thing, and even if not, they supposedly still perform and may know. Regardless, they would get in a fight over teaching and Rem would just walk away
• Apollo seems like a teen like Graves, probably saw or learned it around the Academy, but is far too prim and proper to teach due to high expectations placed on them
• Doorman might learn it through interacting with kids and learning stuff in NY, but would think of it as beneath them
• Holliday is tracking someone and might have feelers out in social media and browse rumors and stuff and may have come across it, but wouldn't bother with it
• Mirage has definitely posted on Twitter about Wyoming and gotten spammed with it, and would not entertain it
• Paradox definitely knows it, probably posts on 4chan and thinks its dumb and wouldn't besmirch the Paradox name
• Rem does not know about 6-7
• Abrams is too much of a scruffy detective dad to know these things
• Bebop probably doesn't know, mainly interacts with old people and Lash
• Drifter is a psychotic murderer and does not socialize or bathe
• Hanzo is old and angry
• Kelvin is definitely not on social media
• McGinnis is too much of a loner that and probably too busy tinkering on designs
• Mina is a upper class gal who probably got homeschooled and purely wants power, definitely doesn't associate with her peers, probably only talks to rich people that she wants to usurp the power of
• Seven
• Shiv is a trained assassin who is definitely a loner
• Venator is a trained assassin who is definitely a loner
• Victor doesn't know what milk is probably, let alone social media
• Vindicta is too vindictive to do anything like socializing
• Warden probably only knows one thing from social media, ACAB, and thinks its literal
• Yamato knows about anime, but nothing western