Whats the point of difficultys?

[Mitrell]

Why are there more difficulty, and why even do them? I get it you can get gems, and more gold and thats it.
There is no quests and there is no better gear or material drops on the other difficultys.
I think you need to make more rewards for doing those. It takes a hell lot of time doing all maps 5 times on each difficulty.
I do it for the gems, but its not fun at all. Its just a long tidious grind for a few gems.
There should drop some of the rare crafting mats since theres is not enough of them overall.
And the shop only offers item the first week then you cant buy anything also.
The shop could also continue sell material boxes and stuff for gold as it do while leveling up.
The game sort of stops after completing normal act.
And im done with all the season battlepass aswell.