I think the idea is to disperse to other instances. If lemmy.world has 70% of users then it makes a bigger target for attack.

If we are dispersed then, even if lemmy.world goes down it would only effect a small portion of your feed.

Either way, the more spread out our net of users is the stronger the fediverse will be. I am going to move instances myself, although my content will still be viewable on lemmy.world. such is the power of the fediverse