In Egan's Diaspora, post-biological humans live as software in vast computational structures called polises. One millennium in, the Fermi Paradox is still unsolved — because uploaded civilizations discover that moving to another star is prohibitively expensive in information terms. The galaxy's silence has a bandwidth explanation.
At 17,000 light-years, transmitting even a small polis to Omega Centauri from a neighboring system takes on the order of the current age of the universe at any plausible bandwidth. And the reverse — a polis already in ωCen transmitting to us — faces the same constraint. Post-biological civilizations that arose in ωCen 10 Gyr ago would have rapidly discovered that interstellar communication at polis scale is economically irrational.
What we'd expect to detect instead: local computation signals near the host star (waste heat, structured EM from tight computational clusters), and nothing beyond a few light-years. The absence of large-scale colonization signatures from ωCen is consistent with this model. We are not looking for an expanding civilization. We are looking for a very efficient one that decided, long ago, to stay put.