Indeed. The idea of Orion as a glorious and advanced empire of the past, now in ruins, is very much a canonical one, from "What Are Little Girls Made Of?" before it made it into "Yesteryear"; in that sense, FASA material doesn't offer all that
much original content. It just combines the slavery angle with the ruins angle, something the writers of further material would probably have been prompted to do in any case. But it all holds together pretty well in retrospect.