If space travel were performed only by robots (and really, why would anyone do it any other way) then large scale “colonization” need not even make sense: the r

If space travel were performed only by robots (and really, why would anyone do it any other way) then large scale “colonization” need not even make sense: the robots could travel around at sunlight speed doing whatever research is of interest to the aliens and gathering whatever resources are needed for people on or near the home planet. “People” might have long enough lifespans that the time taking by the robots to travel around might not feel significant, especially as it would mostly be happing in background.