I no longer use anything with posts and likes and a feed, but direct and small-group messaging are pretty important among my peers. May I ask what generation are these people with whom you use only voice (and maybe snail mail)?
That's a good distinction between diff types of messaging.
I use email and messages as well, but the voice call is the big component. Generation-wise, it is from 7yrs old (nieces) to 90yrs old (no surprise there; oldies love to chat).