The theory goes something like:
Any alien life that comes to earth has to be more intelligent than ours because they have mastered interstellar travel where we have not.
I don’t think they apply that line of reasoning to finding any kinds of life on other planets. I mean, no one is saying that some bacteria on a planet 300 million billion miles from here is more intelligent than us.
More intelligent than the liberals, maybe...but not us.
And just WHO is to say they have mastered interstellar travel????
Just the same , old, eugenics philosophy.
Visiting aliens wouldn't have to be any more intelligent than humans to have mastered interstellar travel. Their cultures would simply have to be older. We'll likely master interstellar travel ourselves (provided we don't kill ourselves off first) within another hundred years.