I don't know if it's a fair knock on Ep.III that we don't see Anakin making the Graflex saber or that there is no meaningful focus on it. I think it's value in the saga is simply the physical connection Luke can have with his father he never knew. So the "Excalibur" element really doesn't become meaningful until the OT and now more so in the ST.
There should have been some sort of connection between Anakin and his children before he started to turn to the darkside.
There should have been some sort of connection between Anakin and his children before he started to turn to the darkside. The saber could have served as great device in telling that story.
My fan theory is that GL knew full well that he was going to make the PT horrible. Everyone always gives him flak for seeming disinterested and lazy in the BTS footage, but what if he just really didn't care? What if it was all a plot to advance both digital and physical effects to the point to where he could make his REAL vision? The movie he REALLY conceived 40 years ago?
That vision? The Force Awakens.
George turned ROTJ into a joke with the Ewoks and turning Fett into a (once awesome character into a silly character)... He was already into the mindset of "Star Wars is for children"...Which is BS.