Valve has explained why it is bringing Half-Life: Alyx to VR rather than traditional platforms.
According to developer Dario Casali, the main reason was the number of possibilities that virtual reality provides. Speaking to Geoff Keighley in a YouTube interview, the designer detailed how VR controls allow for more player choice and interactions in Half-Life: Alyx.
“The more we used the controllers and the headset, we realized the amount of interactions this gives, the amount of possibilities these things give us,” said Casali, “When you can track your hands separately from your head, they’re all 3D space, all simultaneously tracking and moving, you can’t really get that with a mouse and keyboard.”
One idea that Casali gives as an example is the ability to carefully manipulate a door. Users could use one hand to nudge the door open while firing into the crack with their other hand. Such a mechanic is not something the team would necessarily be able to translate well to traditional keyboard and mouse controls.