The immortals step back and realize that they've been sent away. They're worried about the future, but they don't want to destroy the immortal world. The world needs a strong force to protect everyone and maintain order. If there's no strong force, people will use it to their advantage. This is why many people have lost their lives because of the power of the immortals. If the world doesn't have a powerful force, it's not worth sacrificing a few people to keep it strong. It's better to sacrifice a few than a lot of people. The most important thing in life is not how strong your power is, but how brave you are to face the world for its sake.