It would break most of how the internet works today. It would prevent most forms of real time, one to many, communication since a human would first have to moderate it.
Best example is public audio/video conferencing. I watched a conference presentation in real time today, which had real time comments in IRC and an audio/video conference question and answer. Neither of which would have been possible if real time moderation was required.
How would moderation even work for audio/video conferences? As far as I can tell it would not work since no moderation could happen in real time and allow for smooth audio/video conferencing. What if we act as a platform though and claim no responsibility for the content that happens? Then there is no ability to set topics or restrict offensive material etc so any random person(or bot since how would you tell the difference) could streaming in offensive videos or loud noise
Loosing most, one to many, real time communication would be throwing out a considerable amount of value.
Do you have solutions for issues like that?
edit clarifying that I am taling about one to many real time communication.