Keening is a tonal item and Dwemer are famous for tonal magic. I'd be found a fool to say that keening will never have a purpose again.
Keening in full power will kill you instantly, you can not even handle the tools without Wraithguard on, or at least you shouldn't be able to.
Which leads me to believe that either the weapon is a fake, but that's kinda strange considering the outcome of the quest line where in you get it, or alternatively that it has weakened an incredible amount of the past 200 something years.
If Keening were to regain its strength then the hero of the story would die, so Keening won't get another use in this game. Perhaps in a future installment, but it and the heart will probably play larger roles then.