This statement comes up all the time as if it automatically wins any discussion of alien civilizations. It contains a number of huge possibly specious assumptions. The first and most obvious is that even a long-lived civilization could construct a technology allowing a non-trivial amount of mass to accelerate to 0.1c and more importantly decelerate at the destination to a relative velocity of zero to facilitate the colonization.

Also your timeline presumes self replicating spaceships exist or could exist. Have you ever thought about what kind of spaceship could mine metals, smelt them, make glass, build a chip fab etc?