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I assume there is something in the canon, written 15 years ago, along similar lines, but here is a thought:
Assuming the resolution of the Fermi Paradox is that advanced alien civilizations exist, but choose to say hidden from us (for whatever reason), the most logical point of breaking the cover would be as humanity approaches ASI. It seems that ASI comes earlier in the tech tree than space travel or similar technological breakthroughs that would also warrant breaking cover.
The corollary to that is, of course, that when the first civilization achieves an aligned ASI, this triggers the race for the light cone to prevent others building unaligned ASIs.
So, if P(saved from ASI by aliens|advanced alien civilizations exist and are close enough) is high (e.g. 95%?), what is P(saved from ASI by aliens)?
This might require an alien ASI that only pursues prevention of ASIs and doesn't exploit the cosmic wealth, otherwise the stars would be going out. Alternatively it could be falsifying astronomical observations and human eyesight, which is close to humanity living in a simulation outright.