If you read between the lines in Osbourne's latest Q&A, you'll be able to figure out the reason why. I'm paraphrasing, but Osbourne said that OoK was a test to see if they could produce good quests faster and cheaper but still keeping the same quality of lore and gameplay. The reskins and asset recycling was obviously what he was getting at. To be honest I didn't mind it at all. There were still enough new areas and characters to make it feel authentic, and most reskins were fine. If that's the case (they're pushing for faster and cheaper quests), I'd say this far but not further. As others have said, the lore kept this quest afloat even though the graphics weren't stunning + reused a lot. The only place I thought about those were during the final battle, being in Guthix' chambre; though that could make some sense. (even though I'd like to have someone mentioning it in the quest why it was the same room). The nice thing about them cutting down on graphics for me is that runescape, even though it's a lot better than ten years ago, for me always have been about the lore and the story, not about the graphics - this quest is kind of keeping in that tradition. Better graphics would of course be better, but I'd rather cut back on them than on the lore and storytelling.