>The thing about the "Great Filter" is that it is great. If you can even imagine an exception for your candidate filter, then it's not great enough.

I don't mean this as a personal attack, but that gets the idea dangerously close to the theory of unfalsifiability.

Personally I am more inclined to the believe that we haven't heard any radio signals from space because you don't run a multi-galaxy civilisation on light-limited transmissions.

Invent the ansible and then maybe we will find the galaxy theming with life.