Putting a freshly discovered intelligent species, that started to use technology for a few hundred years, under quarantine for a few thousand years, makes sense. If they survive, they might be worth bothering with. Otherwise, observation from distance, without interfering/risking massive amounts of energy, is a logical and sane course of action. IMHO.
<i>"alien civilizations would need to network to forge a treaty to leave primitives, like us, in the cold"</i><p>Or they just need to think alike, with no need for a complicated assumption that they forged some kind of treaty with each other. Maybe it's hard to see now, but in a space faring era with enough alien contact it might just come out as an obvious thing to not trust others too much and thus limit the exposure as the first measure of precaution.
Hmm it still doesn't answer the issue of emerging civilizations, we have been sending quite a bit of signals to outer space unintentionally and we still do, and while those signals aren't powerful enough or directed enough for communication they can still be somewhat picked up.<p>I also don't understand how exactly such treaty would be negotiated given the distance and luminal or subluminal communication speeds in a relativistic universe.<p>I'm still of the opinion that the best answer to "where's everyone" is that while life isn't rate, intelligent life is, and technological intelligence is even rare at least at any given moment, and it's quite likely that there are sufficient great filters ahead of any civilization that evolves to make any coexistence of technological civilizations within a given galaxy a rarity.<p>Life spawned on earth virtually the second it cooled down but it took it 3.5-3.8 bln years to develop a life form capable of even basic space travel, a lot of things can happen within a period if nearly 4 bln years and a lot of things have happened on earth where almost all life (and possibly all life) have been erased.<p>Add to that the possibility that earth just happen to form around the time that life was started to be possible in our own galaxy as the younger Milky Way could have been too violent even around the galactic rim for complex life to evolve due to the constant star formation and death and you give even more credence to the fact that we can be first, rare, and doomed all at the same time.<p>I find overall the notion that "we aren't special" to be a slight logical fallacy, it is quite possible that both our universe and earth are very special that doesn't mean that they were created or we are in a simulation it just means that they are special and we live in a special time in the universe where the various constants are favorable for not only atoms to develop but for live to evolve and we are in a special part of the universe or even in a special part of our own galaxy and if not in a special location possibly in a special time.<p>Saying that earth isn't special and hence life is everywhere with a sample of one is like saying that winning the lottery isn't special from a sample of one, saying that earth and the sun are average and if they were special statistically we wouldn't be here also holds very little merit because while statistics do not take sides but if they would not have played "in our favor" we wouldn't be here discussing them in the first place.