I'll just stand here and look at the camera with a concerned look on my face, ok?

One of the things that makes me laugh at times is the expressions upon news reporters faces when out and about in the field doing a ‘live’ report. Depending on the type of story, their facial expressions must be difficult to hold true while waiting for their segment to begin airing.
Some nod their heads up and down while waiting the long periods of time it takes to transmit and be recognized concerning their segment from the station newscaster.
They then begin their story, reading notes, or perhaps pausing for a pre-recorded filmed segment, and then that ‘look’ goes back on their faces until they are told to continue with the live portion.
At the end, serious or smiling widely, the station newscaster then closes out the segment with a farewell, or thank you. Usually the reporter is still nodding like a crazy person, or they get their response cut off.
After all of the technology out there- from the moon and back, the depths of the ocean- so far, and “can you hear me know’s” it seems everything is still technologically beating the out the transmission timings on live broadcasts!
Why is that? What has left this segment of communications in the era of “Watson! Come here! I need you!” (Because I just spilled acid on me!) to ” and now, back to you….nod….nod…..nod….look at camera without blinking…...nod…....????