Another possible resolution of the Fermi paradox based on the many world interpretation of QM:
Let us assume that advanced civilizations find overwhelming evidence for the many world hypothesis as the true, infallible theory of physics. Additionally, assume that there is a quantum mechanical process that has a huge payoff at a very small probability: the equivalent of a cosmic lottery, where the chances of obliteration are close to 1, the chance of winning is close to zero, but the payoff is HUGE. It is like going into a room, where you win a billion dollar with p=1:1000000 and die a sudden, painless death at p= 999999:1000000. Still, for the many world hypothesis is true, you will experience the winning for sure.
Now imagine that at some point of its existence every very advanced civilization faces the decision to make the leap of face in the many world interpretation: start the machine that obliterates them in almost every branches of the Everett-multiverse, while letting them live on in a few branches with a huge amount of increased resources (energy/ computronium/ whatever) Since they know that their only subjective experience will be of getting the payoff at a negligible risk, they will choose the path of trickling down in some of the much narrower Everett-branches.
However, it would mean for any outsider civilizations are that they simply vanish from their branch of the Universe at a very high probability. Since every advanced civilization would be faced with the above extremely seducing way of gaining cheap resources, the probability that two of them will share the same universe will get infinitesimally small.
To our perspective, this is from (2): all advanced civilizations die off in massive industrial accidents; God alone knows what they thought they were trying to accomplish.
Also, wouldn't there still be people who chose to stay behind? Unless we're talking about something that blows up entire solar systems, it would remain possible for members of the advanced civilization to opt out of this very tempting choice. And I feel confident that for at least some civilizations, there will be people who refuse to bite and say "OK, you guys go inhabit a tiny subs...
We have a sample of one modern human civilization, but there are some hints on how likely it was to happen.
Major types of hints are:
Data for:
Data against:
To me it looks like life, animals with nervous systems, Upper Paleolithic-style Homo, language, and behavioral modernity were all extremely unlikely events (notice how far ago they are - vaguely ~3.5bln, ~600mln, ~3mln, ~200k or ~600k, ~50k years ago) - except perhaps language and behavioral modernity might have been linked with each other, if language was relatively late (Homo sapiens only) and behavioral modernity more gradual (and its apparent suddenness is an artifact). Once we have behavioral modernity, modern civilization seems almost inevitable. Your interpretation might vary of course, but at least now you have a lot of data to argue for your position, in convenient format.