A quasar, too heavy to be true

On 01 Jan 2018, Gary Harnagel wrote:
G-type stars that are gone now
but the intelligent species "hatched" by them have migrated to a younger
star. At only 0.1% the speed of light, generation ships could cross the
entire galaxy in a mere 0.1 billion years.

But they never came here, to Earth. And yet they would have spread
out over the galaxy, the same as yeast in a Petri dish. What part of
the Petri dish escapes the yeast? None. There is your evidence that
no such alien civilizations exist.