This is more of a question then a theory or lore.
Are the non playable guardians like (the vanguard, Osiris) bound to the same light level system that cosmodrome and red war guardians are bound to? a average level based on weapon and armor levels. Do they even have a light/power level and if so does anyone have any idea what it might be? Like are the just at a incredibly higher level then us or are they at what ever the cap happens to be and when we get a increase its because they raised the bar? Also curious on anybody’s thoughts if our armor and weapons intrinsically have power or are we or some other guardian or ghost imbuing it with light?
As for the NPC’s, I just believe they are meant to be guiding mentors rather than someone/thing with a light system. The Light System is probably just a progression system encouraging players to play (I.e. Battle Pass in Fortnite, Black Ops 4’s Contraband). As for the weapons and armor, I assume that the more powerful we become, our Light becomes infused with them, which might explain why weapons wielded by Guardians (Ace of Spades for Cayde, etc.) are so powerful, because they have our Light and their own? But mostly I would say they are just weapons and armor, because after all, we can use mods and items to boost them, not to mention there is a gunsmith.