Sullo was arranged to be on a planet at the rear, in charge of helping the logistics department transport supplies.
On the battlefield at the front line, one could not casually use the space teleportation ability.
This was because both the enemy and the ally would set up a large number of anti-air barriers to disrupt the space elements.
If one forcefully teleported, it was very likely that they would be swept up by the chaotic space storm and be destroyed.
Even if that did not happen, the other party could still detect them and intercept their destination, changing it.
One could be banished to the void and never be able to return. Or maybe even teleported directly into the enemy's base camp and become their feast for the night.
Therefore, starships were generally used as the main transportation method around the battlefield.