Oh, I misunderstood you. Thought you were saying you've never seen a five star system in NMS, but I guess you were saying you didn't see any system in the most recent videos?
Nah. He did have a sentry attack him(NMS Spoilers for the 26 minute video? @_@), but it didn't summon more sentries nor was there any system that lit up as if he was in danger(Like GTAs system).
It's possible that the crosses were the 'warning system', but they were below his health, looked like medkits, and next to a shield icon(I'm assuming that meant the players shield.) Also, the life support in the inventory had crosses like the 5 under his health(Shield?)
And he was gathering alotta resources, and no sentries popped up