> Try the two with a chess timer
Of course voice will be faster--eight out of ten times at least one involved party's main goal is just to get off the phone.
Optimizing for time is a mistake. Optimize for disruption (I can switch back to other work while waiting for a chat reply--there's context-switching overhead there, but not nearly as much as a phone call), retention (I can refer back to what someone said in chat, rather than "hey, Jane, what was that hostname again?", waiting for an atrocious speech-to-text conversion, or manually seeking around in a call recording), and mutual investment in communication (professional or not, a synchronous call usually has at least one participant that wants to be there less than the other[s]--in chat, people can participate when they're most interested in doing so, meaning that their contributions are less half-assed).
There are situations where sync is best (trying to pitch something or persuade colleagues of something is a big one--it's just easier to reject/be reluctant without engaging critically via chat for some reason). But a lot of the time chat is more efficient.
I've found that many people I've worked with who strongly dislike chat are not practiced or comfortable writers in general, and, after some training (if such folks are willing, I've had them take documentation, presentation-building, or RFC/RFO writing tasks as practice), they tend to be much, much happier about (and better at!) textual communication.