Nah it propagates. I wanna say it goes at light speed, but there is a delay. If this is actually referencing something new, maybe that's different now.
The Fermi paradox is the discrepancy between the lack of conclusive evidence of advanced extraterrestrial life and the apparently high likelihood of its existence.
Correct. However the most popular explanation is that technological evolution outstrips cultural evolution resulting in civilizations destroying themselves before they can attain interstellar travel