You can see how much the hierarchy and taxonomy of producers has expanded since the '60s, when a show typically just had one story editor, one producer, and one executive producer.
Not to mention muddying up the term "producer," which seems to have been chosen for the writing staff because it was the most important sounding title that wasn't restricted by a union contract of some sort.
Still, I think it's an unfortunate blurring of the lines that people who are down on the sets managing day-to-day operations and people who are in the writing room generating the stories both have the same title. While there are some producers who do genuinely "do it all," this is rather rare. I wish there were a better title that could be given to the writers as the moved up the ranks that carried the sense of the import of their role while not confusing them with other areas of responsibility. What David Livingston or Peter Lauritson did is certainly very different from what Ronald D. Moore or Robert Hewitt Wolfe did.