He died to stop the wars, dismantle any army that could kill his people and to make his people the “heroes” that killed him so that everyone would see the marleyeans as heroes instead of titan monsters
That’s how in the end, humanity grew together and the future happened with people creating buildings and living together and growing old and forgetting about that tree just to come right back to it hundreds of years later
OH HELL NO WTF IS WRONG WITH YOU