Yeah but when you pair her with characters who are immune, just like Smoker was, it is a useless ability.
Smoker wasn't immune, I don't recall her ever using it on Smoker, other than just turning Smoker's jitte into stone. Then she processed to kick bunch of pirates and marines turning them into stone everytime she touched em.
Doflamingo's strings? Can't do shit to her, they get turned into stone when she touches them.
Jozu's diamond? gets turned into stone against her in CQC
Want to counter her? Gotta have your CoA on at all times in order to avoid that.
Want to avoid her lust attack, gotta handicap yourself (like Momonga did) before fighting her. Like we don't know which way she turned Devon and Vasco into stone, if it's the other way, then it's understandble, they might've been caught off-guard with not knowing the DF's abilities properly, it doesn't really mean much then.