Time Travel at the Same Time, Why Are They All Hokage?

Traveling through all the worlds at the same time, shouldn't it? Why do countless people go to the ninja world, or to all kinds of abstract ninja worlds? Immortal Forbidden Zone: In order to seek immortality, the strong will self-transform into the forbidden zone and harvest the chakra of all living beings every hundred years. Zombie craze: For unknown reasons, zombies have swept through the ninja world, and civilization is on the verge of extinction. The world of all magic collapses: magic techniques can multiply independently and merge with each other, and the world becomes a slaughterhouse for magic techniques. Utopia: In order to create a long-term peaceful world, the law of heaven appeared in the ninja world and monitored everyone's thoughts. In addition, there are many ninja worlds that are heading toward, or even already collapsing. For example, Capital Ninja World, Endless Reincarnation, Mythical Ninja World, Otsutsuki Total Invasion, etc. When he first came here, Qingchuan couldn't help but complain: I, Zhuowei, have dressed me in time travel, forget about the rest, why is there still an invasion of the void?