1. Eye and face tracking. The author mentions lip syncing and hand tracking. That goes a long way, but it doesn't recreate the video experience to me. There are a few vtubers out there that are doing some seriously impressive tracking, but it requires tons of special equipment at the moment. Once this gets resolved in a consumer model, I think things will really shine for virtual presence.
2. Lighter weight headsets. For longer sessions, a custom headstrap helps a ton, but even still lighter headsets will go a long ways to helping here.
3. Better lenses and better displays. The lower res means you're really forced to work at huge virtual screen sizes, as the author mentions. While this is the least needed item in this list for basic productivity, the screen door effect definitely creates a barrier some of the time.
I highly anticipate that we'll see a sizable portion of the population change over to VR for productivity within ten years. It has huge potential, especially with the remote work environment many are in these days. I would love to be able to feel the presence of people around me again, while still not having a commute or the risks associated with being physically in the same room.