Two problems I’m seeing here.
a) No clear way for the player to know “you are now leaving the previous game-reality”. At least with the Tome Of Eternal Darkness they had to affirmatively read it–still not ideal, but a clear interaction event. Sticking people with this for just grabbing something seems way too harsh. (How else are you going to interact with it? no item-examine whilst it’s on the ground, IIRC.)
Making folks afraid to touch things for fear that they’ll get permanently Screwed–I’ve not seen anything in either of these threads about ways to cure the problem–discourages experimentation. Bad Thing, IMO. If dropping the idol or the Tome lets the penalty-state time out, then I might think about it.
b) Hallucinations are fake and should stay that way. When one’s weapon stuck in them, we considered that a bug. Likewise there’ve been times when hallucinatory critters did do real damage. Bug also. Pretty confident we cured the problem where hallucinations could interact with terrain. There’s a long tradition of “hallucinations can’t affect reality” in Cata.
I’d rather not have to check bug reports for whether or not someone entered this penalty-state, especially when people might not know how or why they did so.
Cultist tip 116 seems relevant here.