Notice that, in Robin’s scenario, the present epoch of the universe is extremely special: it’s when civilizations are just forming, when perhaps a few of them w

Notice that, in Robin’s scenario, the present epoch of the universe is extremely special: it’s when civilizations are just forming, when perhaps a few of them will achieve technological liftoff, but before one or more of the civilizations has remade the whole of creation for its own purposes. Now is the time when the early intelligent beings like us can still look out and see quadrillions of stars shining to no apparent purpose, just wasting all that nuclear fuel in a near-empty cosmos, waiting for someone to come along and put the energy to good use. This presumes that The Most Technologically Advanced Civilization sees virgin nature as nothing but raw material waiting to become something useful. That's possible, but probable? I think that it's likely that diminishing marginal utility still holds even for TMTAC, and therefore they are disinclined to convert all the universe's visible matter and energy into Dyson swarms of Space Product. My favorite (not particularly testable) solution to the Fermi paradox is that TMTAC originated shortly after the first heavy elements and planets formed. It became space faring and expanded throughout the visible universe before our solar system formed. Its agents have been lurking in our solar system since before life first appeared here. Having long ago achieved immortality and technological supremacy, there's no motivation for plundering or trading with terrestrial creatures. They silently observe like space faring bird watchers. They'll intervene if/when we start to approach the capabilities of TMTAC, particularly if we show destructive paperclip-maximizer inclinations toward converting the universe into Space Product. To borrow some terminology from Nick Bostrom's Superintelligence book, it's possible that the universe has been colonized by a singleton civilization -- the first one to become star faring. But it's not particularly chatty or inclined to let potentially competing star faring civilizations expand.