"The prior shows a logical certainty, the latter [absence of evidence] is rationalization."
No, the latter is not mere rationalization; it is a logical use of limited resources (like time and money).
People can come up with a billion crazy theories or stories. We don't have time to test all of them or start using all of them by default. Hence, the responsibility falls upon the story-teller or seller to do the test and present evidence before anyone else gives them attention, time, or money in return. That's not rationalization -- it's simply rational.
As I say in my statistics classes: "The null hypothesis gets the benefit of the doubt; the alternative hypothesis has the burden of proof". (Or as Wikipedia puts it: "Rejecting or disproving the null hypothesis... is a central task in the modern practice of science, and gives a precise sense in which a claim is capable of being proven false. The null hypothesis is generally assumed to be true until evidence indicates otherwise.").