True, but there is also a difference between the story and the plot, and differing opinions on which is which. To me, the basic story is of a guy who started off good, with good intentions, who through a series of tragedies and lack of proper guidance, became something very, very evil. That's not a bad story right there, if a bit cliché.
It's how it all played out that most people have trouble with. I think of that as the plot. Or hell, maybe that's the story and the outline is the plot. Which is which?
I think the story and plot are very much intertwined. I was under the impression that when people refer to "story" rather than the plot, is that the "story" includes the thematic elements in addition to plot. But I may be off base.
The "basic story" you describe of the prequels is one shared by literally thousands of works of fiction. It's not a useful descriptor, because it's so vague and reductive. By boiling down the entirety of what happens to a couple of words, one can make anything sound like anything else, or sound compelling. Just to give two other noteworty (and visual examples),
The Godfather films and
Breaking Bad both share the same "basic story." But they are both very different (and far superior), because when you're working off the basis of something as simple as that, execution is 99%.
If we're going to be this vague, one could just as easily apply the "Well, the core story is good!" argument to loads of other dreck.
Twilight, or
Battleship, or that endless string of awful parody movies, etc.