Gordon was famously mute and his hands and forearms were hidden. This allowed anyone to easily immerse themselves. (Same for Portal.)
Unlike a third person game where you're controlling a character, I could see how having a different voice and hands in VR would be odd. I bet Valve realized that a mute protagonist no longer works in a story-driven environment.
I remember reading various making of stories regarding the half-life world back when it was still relatively new, and even then the designers spent a lot of time talking about how difficult it was having a mute, non-interactive protagonist. What they pulled off is excellent considering the state of gaming at the time, but I think you're right in that it just wouldn't fly today.
South Park did a really good job with a mute character in both of their recent games. It became almost a running joke in how the conversations would flow and the silence was taken as support for whatever the speaking person wanted it to mean, highlighting narcissism or teasing societal expectations.
Unlike a third person game where you're controlling a character, I could see how having a different voice and hands in VR would be odd. I bet Valve realized that a mute protagonist no longer works in a story-driven environment.