“Big brain time” became a widely shared internet reaction phrase through meme pages, short edits, and gaming clips in the late 2010s. The audio version of “Yeah, this is big brain time” spread because it neatly labels a moment as genius, ironic, or both at once. It is still used in compilations and short-form videos because the setup is instant: play the line, show the idea, and let the audience decide whether it was actually clever or completely dumb.