In fact, I would argue that our struggles about the definition of “authorship” in a research context are in fact evidence that the concept itself is outmoded. In the days when most projects were concevied of and carried out by a single person who then wrote up the reports by himself (pronoun being used advisedly), the idea of assigning credit for research to an “author” (in the traditional sense of “the writer of a book or other work”) made sense—though there are enough examples of lab assistants (usually women) not receiving credit for essential work even from those days to make one wonder.
Now that few projects are conceived of an executed in this way, however, the entire privileging of “authorship” (however defined) makes much less sense. It remains important to identify the people who bear intellectual responsibility for the argument and conclusions of a given research communication; but it does not seem more important to me to identify the people who bear intellectual responsibility for the particular set of conclusions as being more important than all those others without whose contributions the “authors” would have nothing to conclude about. In the modern research world, “authorship” (like “writing,” but also like “getting funding” or “developing the algorithm” or “doing the coding”) is really just one kind of contribution credit.