this is the first attempt that we know of to weaponize Guardian relics
It's not. What do you think the "shards" that the Guardian Shard Cannon fires are shards
of?
Ram Tah has already mentioned the areas of thargoid/guardian conflict as on the edges of the known Guardian bubble, so if this is one side of thier "bubble" and say the sites in Hawkings gap are the other side of thier relative bubble, then we are looking well and truly in the wrong areas for the "far away location of habitation"
I don't think that's the right way to look at it. There are small bubbles of Guardian activity around significant nebulae all throughout the galaxy - they were clearly well-traveled. Who knows, maybe those represent colonies established in some Guardian parallel to the human Dynasty Project, as fallback positions in case the Thargoid threat became existential. But the main bubble of Guardian activity is clearly the one near us.
I'd also say that the lore
does set it up as being logical that the Orion region was the locus of conflict between the Guardians and Thargoids. If you look at a map of brain tree locations, it's clear that the Guardians seeded a region of space that just brushes up against the Col 70 locked sector, and maybe extends slightly inside it (see this
fantastic old thread for some extended discussion on that) extending perhaps as far as the Col 70 Sector FY-N C21-3 system that is known to be highly significant to the Thargs. The Witchhead Nebula, which was not known in 2018 but is known now to be a center of Thargoid activity, is likewise not far from the edge of the brain tree bubble. So while the Guardian sites in the Trapezium Sector are quite far from their other known sites, they are not actually all that far outside the known borders of Guardian activity, and Barnard's Loop could very well be the region from which, as Ram Tah found, they were "forced to make a partial retreat". Perhaps the retreat was mutual, which might explain the nagging mystery of why, if Col 70 is so important to them, is there no known Thargoid activity inside Barnard's Loop itself?
Incidentally, the presence of a Guardian Ruin there is also interesting from a lore perspective, if the writers have kept this straight, because our previous understanding was that the Ruins are newer than the Structures, and date from long after the end of the Guardian-Thargoid conflict. That suggests the Guardians came back, if only to establish their equivalent of a communications relay - but not to stay, since they didn't seed brain trees in the surrounding area.