Could alien signals have already reached Earth undetected?

Could alien signals have already reached Earth undetected? - If advanced alien civilisations exist and have contacted Earth, they are more likely rare, scientists say

This Man Says It’s Possible Our True Ancestors Are Aliens. Will the Mainstream Ever Believe Him?

While idea may violate Occam’s razor, “it remains a speculative but logically open alternative,” says biologist Robert Endres.