Proc gen can be engaging if emergent content is complex, dynamic, and novel. But again that goes back to Radiant AI being a vessel for generic fetch quests in the newer games, while in a proc gen game you would think there would be a major, if not the major dev focus on fleshing out the system in other ways (from dynamic tribes and factions to more fully fleshed out STALKER-esque persistent fellow space travellers with agency). The final missing component would be inspiration in design of the pieces, so they interact together in interesting but emergent ways, which is of course another element that the game sorely lacks.