The in-canon explanation is most likely that the suliban were either destroyed in the temporal cold war, simply died out over time, or just became a minor galactic power.

The real explanation is by the time they thought of the suliban the other series were over.

The in-canon explanation is most likely that the Suliban were either destroyed in the Temporal Cold war, simply died out over time, or just became a minor galactic power.

The real explanation is by the time they thought of the Suliban the other series were over.