You're resting the controller in your hand lol. You can't play a game like Beat Saber doing this as you have to maintain a grip, it's the only thing tying you to the controller, no different than a console controller.
If you let go velocity will take over and put a hole in your wall haha.
Index controllers are affixed to your hands as a function of design, they are meant to be gripped and fully let go of doing any action conceivable.
Do you see that palm strap around his right hand? That is tightened down so the controller can't go anywhere no matter what you're doing including letting it go.