The Observer has a rotation system because if someone stays in a place for too long, they develop emotions which can lead to unforeseeable changes. The maximum duration is five years, and this time, Gu Tao requested the rotation on his own initiative. After his departure, the Mutual Aid Society will replace him with another Observer, continuing until the next rotation period.
After Gu Tao sent Bi Qing back to Lin'an, it was time to bid farewell to this world.
Of course, farewell doesn't mean a final goodbye. The beacon here has been recorded, and Gu Tao can return at any time in the future to take a look, but as for when exactly, it's hard to say. The procedures for entering the protected civilization are extremely complicated, and Gu Tao cannot always take special channels. Therefore... he will come back if he gets the chance.
