Out of the loop

Yeah, I knew about the song, but afaik it didn't "catch on" until "6-7 kid" did a thing. And now everyone just makes the reference any time they think of it, because they saw someone else make the reference, not because it's ever applicable.

I have to assume there is a field of study of memetics that draws a distinction between "merely a reference" and "applicable". Ex. When a person refers to the "this is fine" meme, it's because they're invoking a sentiment that is applicable to the discussion, which is socially useful because you can build off of a common understanding instead of needing to lay the groundwork first to be on the same page (insert captain america meme). But when people say 6-7, they really are just saying "this is a thing we both are aware of".

OP is basically asking "when is this meme applicable?" And the answer is, it never is.