* Any kind of deeply nuanced conversation. Telepresence is great for the day-to-day stuff, but not if you actually need to be closely aware of the other person's emotional state.
* Anything intended to foster closer bonds. That's much harder to do over telepresence than in person. That's a basic functions of how social animals work.
Telepresence is great for the vast majority of mundane connections. But it's not at the point where it can completely replace travel. I wish it could, because I'd love to travel less.
There is not a single interaction in which in-person-ness doesn't add value.
Necessary is a different ball game though. That wasn't my beef. My beef is with anyone truly believing that physicality holds no value.