Writing is the superior form of communication.
That is, not writing only, of course. But writing should accompany each significant communication.
Why does writing help?
It forces you to think clearly.
It forces you to establish a kind of thought structure.
It is easier for other people to understand because of the structure.
People can read at their own speed.
People can read whenever they wish.
People can easily save requests until later.
Situations
Meetings
Meetings can start unprepared or prepared. If you send a short written memo before each meeting, people will understand the goal of the meeting, have all the necessary information and have even thought about the topic.
Email
Email can be saved for later, which allows for asynchronous work. It may be an old protocol, but widely adopted it is still the best tool for asynchonous work.
Chat
Even when sending short text through Slack, Teams or Mattermost, the repicient can read it whenever it fits them. Furthermore, you still need to think about how you phrase your requests.
Requests for help
When other people help you, you should make it clear what you specific request is. Nearly all the time, it makes sense to speak in person or by phone first and then send specific information afterwards. This is also a good reminder for the recipient.
Providing information
When providing information, a clear structure is definitely helpful. Even when holding a presentation, sending the info in condensed form afterwards helps people remember your message much better.
Conclusion
Don’t stop calling people. Don’t stop meeting people or holding presentations. But make sure that you message is clear, well-structured, can be remembered and is actionable. Writing before or after the personal interaction is the best form of (complementary) communication.