All very good points. But the problems I find with the Simulation Hypothesis are: 1) it would not be the case that we were alone (obviously) 2) If the part of the purpose of Simulation is to keep this fact hidden, the absence of distance-evidence of ETIs is just too obvious a hole in the ruse 3) Simulation still is so much in violation of the principle of parsimony, that the available evidence suggests that we are in a Rare Earth cosmos.

This should already have happened in other galaxies. — RogueAI

Well, the explanation for that seems straightforward: a) ETI's have only been able to emerge in a durable way relatively recently in cosmological time b) not enough time has elapsed to see the emergence of a Type II civilization, given the time-lag in communication between us and Andromeda (much less galaxies further out).

Of course, a Dyson Sphere might seem to an advanced ETI like Steampunk seems to us; a quaint way of extrapolating about the future. Essential to the history of our species has been the discovery of more and more efficient ways of generating energy; we may be on the cusp of (another) energy revolution, one that makes the need to capture the energy of a star much more trouble than it is worth... also it's worth pointing out, that we won't need energy to keep pace with an expanding population, since the demographic transition strongly suggests that the total species population will go into a permanent reduction sometime this century. The ratio of energy available per person may soon be off-chart. It makes sense further to say that "we" biologicals might never engage in interstellar exploration & conquest, instead that will be left up to Homo Superior who will replace us.

Of course the Elder-hypothesis is highly unlikely, but it rises in probability as we eliminate alternative explanations. I don't think the "Rare Earth" hypothesis is viable. Almost certainly there are civilizations advanced beyond us in other galaxies, but at inter-galactic distances (esp with an expanding universe) there is not even the theoretical possibility of Contact with them.

Ironically enough, I think a future-Filter explanation is part of the reason why we are (probably) among the Elders. I've read that earlier in the history of our galaxy, the neutron-star collisions needed for trace-element nucleosynthesis were more frequent than they are today; and the gamma-ray bursts associated with just those energetic events would wipe out existing life anywhere within a considerable portion of the galaxy that was in the vicinity of these events. It might well have been the case that complex life and even civilization arose in the relatively recent cosmological past, that was dispatched in this way. Just as in the way that life on Earth emerged soon after meteor-impact abated enough to make it possible, intelligent life emerging now and hereafter has a more stable cosmological environment to develop in.

It's likely of course that we are not the very first; as I said, we can say that notionally we have one to two dozen ETI's roughly contemporary with us in the The Milky Way. Just as in the case of the Age of Exploration in the history of Earth, those civilizations that become interstellar space-faring civilizations first will have the ability to subject the entire galaxy to an imperial conquest.

Aside from the highly intriguing accounts (by US Air Force personnel) of encounters with AAV's in recent years, Fermi Paradox considerations are making it seem more and more a mystery why we haven't discovered evidence of any ETI's. Barring radical explanations (such as we are in a Simulation, and its parameters don't include any First Contact events), its seems that there is a "Great Filter" somewhere... Unfortunately, that Filter seems to lie in our future not in our past, since it appears that life will emerge quickly given the presence of the slightest habitable conditions. But my take on that is that the situation we are in is unique rather than dire; it can be argued that the presence of the trace-elements that are necessary for the metabolic pathways of complex life take a number of star-generations to elapse before they can be built up in concentrations sufficient for such life (specifically, generations allowing for energetic events like neutron-star collisions to occur, which are necessary for the nucleosynthesis of the needed elements). All this suggests that we are probably "alone" (though we may have a couple dozen rough contemporaries elsewhere in the galaxy) - meaning, we are Elders, we're the ones who can strike out into the undiscovered country of the galaxy and make its real estate our own.