with the virtuality all of earth's land now allocated to states, how might the number of states might increase in the future?

fragmenting states artificial landmasses

Explanation:

There are several ways a new state could form even if all of Earth's land was allocated to current nations. One of the possibilities is that a current state fragments to form two (or more) smaller states.

Another possibility is that nations construct artificial landmasses or habitable platforms in the oceans that are independent countries. Finally, in the future it may be possible to settle the continent of Antarctic if the Antarctic Treaty is ever not renewed.