NPC has become shorthand online for a character or person who seems to follow a script instead of thinking for themselves, a joke that grew out of gaming culture and spread through TikTok, Twitch and short-form memes. The sound works as audio shorthand for that idea, letting a creator signal the joke in a few seconds without explaining it. It is still used because the reference is instantly understood by gaming audiences, and because repetitive, deadpan delivery keeps showing up in real life, from scripted replies to awkward small talk.