Then theres the fact that even the big tribes in 22 are cobbled together from people who dislike each other, just slightly less than they dislike the enemy. And then theres the people like Saint and Tony who own k's but won't join the big tribes for various reasons. I agree with Dark, we've got a year or more left here at least.
^ this.
When worlds like W12 were in existance, things like W21 were regarded as myths and future worlds (I recall seeing it somewhere in a screenshot, I forget where).
W22 has only been going for about 25 months, W12 has been going for about 32 months. W12 has managed to come together surprisingly quickly, but the way things have been going so far, I am doubtful this world will end for another year or two. The winning tribe will literally have to control the entire world. XXXX would have to noble out the entire world basically.
Unless numbers of people in the world start to dive down to extremely low levels (like less than 100 players), the above circumstance is only circumstance they will close it under.