Honestly, I think the reason so many people can't do the Maven is because the fight is such a clusterfuck of monochrome visual spam that it's just completely unfun to learn. Hence, most of us never do it. Hence, it's hard.
Shaper has attention checks, arena management mechanics, and quick kill skills, and it's not a fight you hear people complain about anywhere near as much. It's usually pretty clear when you screw up, and generally not difficult to figure out why.
With Maven you hit the dirt (because her one-shot mechanics are substantially harder than Sirus'), and wonder which of the same-colored beams/balls/things did what to you that you died so quickly.
On top of that the memory game and spinning beams force you to visit the entirety of the arena you've had to manage until that point (fish memory aside), which is a very punishing mechanic that'll nail you for errors that happened quite a while ago in the fight. In most other fights, errors punish you relatively fast, which ironically feels much fairer.
Sirus had several iterations of changes. The idiotic storms have been changed to the point that now they actively move away from you as you transition between phases. Maven's going to need some serious looking at and get a similar treatment or it's going to have an even lower participation rate than Sirus. Even getting to her is more of a chore than Sirus is.
On the other hand, with Awakened gems gated behind her, I expect the Writs to sell for some serious cash, since the people who have mastered the fight are going to make a killing with them. Maven-exclusive awakened gems will sell 2-5x their current prices (totally random prediction based on nothing but my gut feeling).
I don't understand why they removed the Awakened gems from Sirus tbh. They could have added them to the Maven and left Sirus and the conquerors as is. If Sirus is easier to get gems from, the price of the fragments will reflect it in the open market anyway so it'll balance out.
