If ASI is non-dominating, then an empty sky requires a double explanation: both biological civilizations and the ASIs they create must usually either choose not to produce a detectable footprint, or fail to do so.
The biological part seems especially implausible. Extrapolating from human history, it is hard to expect biological civilizations to be uniformly restrained, coordinated, or low-impact over long timescales.
A dominating ASI makes this less surprising. Compared to biological populations, it is much more plausible for a dominant ASI to have coherent long-run preferences and enforce them consistently. So if such an ASI prefers a small footprint, that helps explain a boring sky with fewer assumptions.
If ASI is non-dominating, then an empty sky requires a double explanation: both biological civilizations and the ASIs they create must usually either choose not to produce a detectable footprint, or fail to do so.
The biological part seems especially implausible. Extrapolating from human history, it is hard to expect biological civilizations to be uniformly restrained, coordinated, or low-impact over long timescales.
A dominating ASI makes this less surprising. Compared to biological populations, it is much more plausible for a dominant ASI to have coherent long-run preferences and enforce them consistently. So if such an ASI prefers a small footprint, that helps explain a boring sky with fewer assumptions.