From the "outside", it doesn't end. But consider world A and world B. They are pulled apart from interacting with each other, so they can't do anything to the A

From the "outside", it doesn't end. But consider world A and world B. They are pulled apart from interacting with each other, so they can't do anything to the A-B superposition like they used to. From inside world A, the entanglement seems to have ended because no matter what scientists(world A) do to coin_1(world A), it doesn't affect coin_2(world A). Likewise in world B.