Historically, how many subjects of scientific inquiry cannot be said at some point to not have a credibly naturalistic explanation, and were attributed to the action of some external intelligent agent?
True that many subjects in past centuries have been attributed to intelligence, or even deity, that later came to be understood as having a naturalistic explanation (an eclipse for example).
But regarding complex, specific information, we have numerous examples, experiences, and knowledge how information of this type comes about—and it is, and has always been, without fail, the result of an intelligent cause. We see such everyday.
So there is an explanation (intelligence) for the observed cause (origin of information). We could not say that about an eclipse because we had never seen an intelligent agent cause an eclipse or celestial event. So to prescribe intelligence to a celestial event was to reach for a mechanism that had never been observed. Not so with information.
Perhaps some naturalistic explanation will be demonstrated conclusively someday for the origin of the first biological information. Right now there is no naturalistic explanation. However, we do know a mechanism for how information arises, yet, strangely, to put this on the table as an explanation for the information in DNA is somehow prohibitive.