Excellent point, there's only so many actual stories to tell, or so the story goes...but I'm not sure we're talking about the same thing.
It's the same way with musical theater as I recently found out while writing songs for a BMI workshop (which I didn't get into) - almost all musical theater is based on an existing story.
But there is a difference between a retelling of one of the stories humanity has always gathered 'round to hear, and a remake of one of those retellings.
Again, most of Shakespeare's plays were
remakes -- not just original tellings of classic themes and structures, but actual retellings of existing stories with (roughly) the same titles, plots, and characters, or fictionalizations (often grossly so) of real historical events. Not to mention all the Greek playwrights whose plays were retellings of existing myths. Sophocles didn't invent the characters of Oedipus, Jocasta, Antigone, and so on; he retold the existing myths about them in a new form. So it's a spurious distinction. Remakes, retellings, they're all part of the same continuum, the same human creative instinct to keep old stories alive.
And yet it still doesn't seem a spurious disctinction to me regardless. Star Trek
was sold as a western in space, its characters based on existing ideas, but it was an original take. Star Trek 2009
is a hyperactive interpretation of those characters.
No, it isn't a spurious distinction at all
from the point of view of the "genii", of generative creative power. Works that have that spark of originality have tapped into it, ones that ride on their coat-tails can be entertaining, but simply don't have "it". This gets into the subjective deep end, but can also be seen plainly with comparing something like A New Hope
to The Phantom Menace.
It's what was referred to when the question was asked all those years ago, "can Gene Roddenberry catch lightning in a bottle a second time?"
What is spurious is implying that all remakes are lacking that spark. If everything is essentially a remake, then the spark of genius is another factor altogether.