The point of the essay is to describe the context that would make one want a hyperphone, so that
one can be motivated by the possibility of a hyperphone, and
one could get a hold of the criteria that would direct developing a good hyperphone.
The phrase "the ability to branch in conversations" doesn't do either of those.
Quoting another comment I made:
Make a hyperphone. A majority of my alignment research conversations would be enhanced by having a hyperphone, to a degree somewhere between a lot and extremely; and this is heavily weighted on the most hopeworthy conversations. (Also sometimes when I explain what a hyperphone is well enough for the other person to get it, and then we have a complex conversation, they agree that it would be good. But very small N, like 3 to 5.)
That seems dependent on it being difficult to scale the specific skill that went into putting together the experience at the good restaurant. Things that are more scalable, like small consumer products, can be selected to be especially good trades (the bad ones don't get popular and inexpensive).