Definition Object: "A material thing that can be seen and touched."
People are material things that can be seen and touched. We are objects – who shouldn't be objectified. But that's a different can of worms.
Even a strict reading of the power allows it to be used on people. I suspect that they were purposefully vague because different groups will want to treat this power differently. It's as much a question of gaming personality as it is a rules question.
No PC is gonna be OK with Darth Vader ripping his weapon away contemptuously. Yet we see it in Empire. In the movie it's dramatic and makes it clear that Han is hopelessly out matched. In an RPG we've taken away player agency and removed all interesting choices a PC might make.
Medium is the message. So what works in a movie may not work in a game and vice versa.
Few GMs will want the big bad evil guy to simply have his lightsaber yanked away by a PC. We never see it. The rules of the game allow it. This is one of those things Players and GMs will have to agree on. My opinion is: You can use force disarm to steal a rival's or a minion's weapon. You can't use it on a Nemesis.
For GMs who are worried about your rivals getting beaten up too easily, remember that you can always add more until the fight is as hard as you want it to be. Bastards have brothers (and cousins, parents, friends, lovers, and Broke-Back Mountain style lovers, etc.). You can have as many, "You shot Kenny!" moments as you like.