I have found 3 Precursor systems so far in my game and lost a survey ships discovering each of them which seems to have been an amazing lure for raiders. As all 3 systems have various wrecks scattered across them like 8+ in each.
Precursors are still pretty scary to my empire tech and tonnage wise which makes it even funnier that the raiders get wiped out by my ships but still show no fear going after their worlds.
That said their are a couple of Precursor wrecks in those systems and when I did a scout of the systems to see what was there I didnt have missiles fired at me in one. I am kind of worried the raiders have just been using wave tactics to make them run out of missiles and are then going to go salvage the wrecks to jump in tech before coming back to wipe me out. so much so I am currently in the process of building a whole new generation of combat ships designed to fight Precursors so I can salvage them first lol