The phrase itself is casual slang for promising support, with gotchu as a shortened form of I have got you and homie meaning a close friend. That everyday meaning is why the clip travels so well online, where short reaction sounds are reused to answer a plea, back up a joke or signal loyalty without a long explanation. Creators tend to pair it with fails, saves and friendly rescues, because the line turns a small moment into a shared joke about having someone's back. Its brevity keeps it easy to drop into edits, duets and comment replies.