Because the wish of ET life out there moved to religious trajectory a long time ago.
Pardon me for being a curmudgeon, but all this well-circulated story amounts to is a very bright physicist warning us about beings that, with respect to hard scientific evidence, don’t exist. Why not caution us against contact with leprechauns, Stephen? Must be time for more SETI funding.
Oh, yes, he cites the “numbers” in his favor. Ah, yes, it’s about the math. By “numbers,” I hope he’s come up with something other than the blessed Drake equation, which is nothing more than imagination and wishful thinking. I’ll file this in my “things many people will take as evidence for alien life that is no such thing” folder.