The old explanation for saber colors also provided the groundwork (albeit probably unintentionally) for a fairly elegant headcanon explanation for why we (mostly) only see blue and green lightsabers in the prequels despite the EU having a way bigger variety – maybe those are the only colors of crystal that grew on Ilum, so Ilum being the only place the PT-era Jedi took students to build their lightsabers could have served as another sign of how stagnant the Order had become in its last days. Then Luke’s New Jedi Order develops a broader range of lightsaber colors again through exploring the full range of Jedi history and tradition.