Maybe 99% of the habitable planets in the galaxy have been sterilized by unfriendly AI and we owe our current existence to the anthropomorphic principle.

Anthropic.

DEATH owes his existence to the anthropomorphic principle.

Maybe 99% of the habitable planets in the galaxy have been sterilized by unfriendly AI and we owe our current existence to the anthropomorphic principle.

Wouldn't we see evidence of this?

Maybe highly rational entities decide large-scale interstellar travel is suboptimal.

I think this is an under considered explaination. Once you get more than 10 light years away ( and maybe much sooner than that) coordination is hard. You can't send messages back and forth quickly, you can't synchronize views and conclusions quickly etc.

Maybe the Agi or civilization or whatnot thinks of starting a colony, realizes that after it does so there will be 2 civilizations or 2 AIs and decides that the increase in the odds of conflict after going from 1 to 2 don't justify the benefits.

Or maybe the Planck mass changes over time, as suggested by Chrisof Wetterich recently and only recently reached a level where life or intelligence suddenly became possible everywhere in the galaxy?

That cannot presently be known, although it's fun to speculate. But I think it helps us more if we can eliminate real-seeming possibilities.