Thank you for another brilliant article.

If we were to make an assumption that no civilization (ours or some distant alien civilization) could ever build a crewed spaceship that would exceed 10% of light speed, I think that means that we or they could never reach a location more than 1.8 billion light years from the starting point. In that case, every civilization is extremely limited to the number of galaxies that they could physically reach in their own tiny corner of the universe.