By the time the Es Civilization receives the news and finally has the time to act, such an interstellar pirate fleet would have already escaped to unknown parts.
"Full retreat at maximum speed!" The Ma Sect emphasized the core command once again.
Any ship that could escape should do so.
If they really are interstellar pirates, they won't pursue total extermination, because destruction isn't the goal, plundering is. As long as they can loot the majority of the population, they won't care about small numbers, and they'll have to leave people behind to guard the spoils. With these factors combined, some are given the chance to escape.
And Shen Shi indeed had no intentions of complete extermination.
The reason is quite simple.
