You also have to be "all in", so to speak, in order to participate. I can window or minimize a screen on a PC. I can pause a game on a console. I'm immediately aware of my surroundings in both cases. With a VR headset, I have to physically remove the headset before I see where I am within physical space.

It feels so silly expressing this, but the act of putting on a headset that completely engulfs my vision with screens, even if my space is already clear with a boundary, feels like a much bigger commitment than opening Steam. It doesn't matter if I'm standing for room scale or if I'm already seated with the headset next to me. Both cases feel like extra effort for a lesser experience.