That's because jagex has been mostly focusing on quests that finalize a long series which are usually locked behind a ton of requirements. I wouldn't mind if they start a new storyline which could end up as a legacy like what most people enjoyed from the elves, gnomes, and pirates despite the recent ones to cap those off being quite lackluster. I think they should focus more on new quests until they are serious about making a good ending with the long storylines we currently have.
@ KijinSeija - Not sure why you felt the need to gravebump this thread to flame others for there responses on a total separate thread, about a total different quest. As it was flaming, it has been removed and this thread locked to prevent additional gravebumping.