What the fuck indeed. When I checked my main spec's artifact I was so disappointed - is this dagger a joke? This garbage needs to be recycled. Disc and holy priest artifacts are amazing though (especially holy).
I guess Im in the minority here but I do like the Old God style dagger that Shadow gets, I mean I would not say no to a staff but I like the design so doesnt bother me.
The two dominant aesthetic inspirations for WoW are Disney and Warhammer, and as the latter's name implies it's all about War. Even the crafting professions all funnel into the war machine, the quests and lore are predominantly war related, etc. Books just aren't very warlike, while Staves *are* warlike, at least in the context of a priest.
I'd give that to you if the class was called clerics and used staves in melee range.
As it is however we stand at the back and cast spells, so at best the staff is a focus, at worst it is only of use for the elderly.
I for one use my spell book much more frequently than I use my staff to hit things or even just take if off my back.