Is being sentient or having a civilization actually required though? Given the wide variety of environments where life can reproduce, shouldn't even non-sentie

Is being sentient or having a civilization actually required though? Given the wide variety of environments where life can reproduce, shouldn't even non-sentient life eventually escape into space? This removes many of the 'great filter' arguments. This would be more likely on a planet with a shallower gravity well than earth. Life, even bacterial-level life tends to spread out exponentially as resources allow, which should make it easier to detect.