Speech is the highest bandwidth mode of human communication
And it's not even close
Let me qualify: voice communication is the highest bandwidth beyond line of sight mode of human-human communication for emergent, unstructured environments, absent brain-computer interfaces.
A decade from now, Special Forces commandos will still speak into their headset during a nighttime raid. Sovereign leaders will pick up the phone in times of crisis. And pilots in congested airspace during critical phases of flight will continue to communicate with air traffic controllers using their own voice.
On March 23, 2024, a Southwest Airlines 737 on the ILS approach to La Guardia experienced a wind shear event on short final, causing the aircraft to deviate below and to the right of the prescribed glidepath and putting them on a collision course with the airport's control tower.
Just 16.6 seconds before a collision would have occurred, a new controller’s voice can be heard instructing the aircraft to initiate a go-around. Importantly, this command presumably came from a controller who was not officially staffed to be controlling SWA147, but chose to jump in to address the emergency. Similarly, the controller can be heard saying “GO AROUND! GO AROUND,” a command which carries far more urgency when spoken in this way.
Today, datalink technologies such as CPDLC are effectively replacing voice communications in aviation for flight plan clearances and command-control in en-route phases of flight.
Still, for as long as humans are controlling aircraft in complex airspace, we’ll use the highest-bandwidth mode of communication available to us. For the forseeable future, that will be speech.