Somebody pointed out that the concept behind SHINee's Replay is...

It's not that deep

huh? "noona" could be used on anyone who isn't born in the same year as you, so the song could apply to someone even a year older than the youngest member, taemin, who at the time was 16 which would mean he could have been pursuing a 17 year old. its the performative "wokeness" for me.

I don't think so.

Like others said, older doesn't mean "significantly" older.

"they spilled"

no, they did not.

Ridiculous reaching

That’s not how it works tho. Noona can be a year older or even two years older - we see this all the time with Kpop groups..