He is right about that, I suppose.

[Or well, knows. He's seen that moon after all; floating high over the castle in The World That Never Was.]

...I can only tell you what is happening in my worlds... though Xemnas' wording suggests that it's also happening in your set of the worlds as well. Where I'm from, the Organization's main goal is to gather the Hearts of the Heartless... and use them to create Kingdom Hearts.