Fair enough has long been a common English way to accept a point without fully agreeing, and that everyday familiarity is what makes the clip so reusable online. Short reaction sounds like this spread through meme edits, gaming clips and short-form videos, where a quick spoken response can replace a caption or a facial expression. Creators keep returning to it because it is instantly understood, even without context, and it softens a joke rather than escalating it. Its brevity also makes it easy to drop at the end of a scene.