The yee comes from Dinosaur Adventure, a low budget animated film by Dingo Pictures known for its awkward dubbing. A short exchange between two dinosaurs, ending in that earnest reply, was clipped and shared on YouTube in the 2010s, where it became a meme. Remixes, reenactments and edits spread the line far beyond the film, and the dinosaur's face and voice became shorthand for cheerful agreement. It is still used because the delivery is recognisable in a second and works without any other context.