SYFM spread as internet slang long before it became a reusable sound, with the initials letting people deliver a harsh shut-up line in a censored, shareable way. As short-form video and meme soundboards grew, clips of someone saying it were clipped and reposted as reaction audio, separate from any single original post. That keeps it useful today: the meaning is understood instantly from the letters alone, so creators use it as shorthand for disbelief, annoyance and playful disrespect without needing any setup or context beforehand.