Sounds close to anarchy to me. Anarchies, historically speaking, do not survive. This would be more pronounced (not less) in case of thousands of inhabited systems, of which many would rely on others to provide food, medicine, certain technologies indispensable to space flight, etc.
Logic dictates that in certain systems, anybody attacking peaceful traders would immediately be hunted down and killed, no questions asked, no response expected, as to turn a blind eye would imperil the entire populace.
This has nothing to do with law of the jungle, and everything with society protecting itself from disintegration (and death). Unless all systems are self-sufficient* (kinda doubt that), at least those systems importing food (and other vital stuff) would be, quite literally, forced to control the trade lanes, or perish. Those exporting food and goods would also lean towards heavy-handed law enforcement, as otherwise, visiting traders would either perish, and therefore, be unable to trade, or stay away in droves, and also impoverish the system.
*Even self-sufficient systems would have to protect their space lanes. There is simply no room in societies for "murder-hobos;" the only ones who condone such behaviour usually apply narrow frames in which it is allowed (being encouraged, under a certain ideology, to brutally murder your (supposedly) unfaithful wife in public comes to mind). There is no other avenue; it is bad enough in a society with simple weapons, which, at most, can only take out a handful of people. A murder hobo, however, who takes down ships carrying vaccines against some kind of deadly disease, could potentially put millions at risk. There would be absolutely no way any government (not even an "anarchy" (an oxymoron; a government CANNOT be an anarchy, as that means, literally, "no rule")) would permit this. The game's explanation that somebody is being shielded from being reported makes sense, but in any other context, realistically, any such person would be dead meat.
Historically, the most brutal punishments were reserved for those disturbing the peace and threatening merchants. In medieval Germany, for instance, robbers would "put on the wheel," i.e., the bones in their limbs would be crushed with a heavy cart wheel, then their (now flexible) arms and legs would be put through the spokes, with the torso and head resting in the centre, providing, and I quote from a book about that (translating on the fly), "noisy entertainment for the spectators expecting a good show." As I have said, in societies that have taken to the stars, this would, again, be necessary to enforce to the hilt.
I'd agree that some regions (should) conform with that, namely, anarchies, which, however, due to that condition, would be extremely unlikely to prosper, as everybody would fend for themselves and not care about others . . . which, as I have pointed out, is deleterious to civilisation.
Edit: Pirate systems might call themselves anarchies, but to be true anarchies, they would need to be ungoverned, with no clear leader, not even a committee. NO rule, remember?

That would make them extremely weak, as nobody would take orders from anybody else, i.e., they would be crushed easily by rival gangs that are actually organised.