This is a neat idea for an article, and a good exercise in thinking about the future of power. But the actual ideas suggested are silly.
Using a sound system to drown out a speaker isn't exactly cutting edge, and delayed or chopped up live audio would be no less disruptive to the event than blasting polka music. As for noise cancellation, it just doesn't work that way, unfortunately (or fortunately, I guess!). You need a known point where the sound waves will overlap in a predictable way, and you calibrate your "anti-sound" to that exact point. Everywhere else, your "anti-sound" is just the original sound replayed.
Directed ultrasound is cool tech, but protest disruptions aren't exactly press conferences. You're talking about someone yelling a simple, pre-scripted slogan in the midst of a lot of noise - a little voice in their ear wouldn't even be noticeable, let alone distracting.
And "false flag chanting", really? Protesters who infiltrate a corporate meeting didn't just wander in there following a crowd, they're not the suggestible sheep you think they are.
As for the projection stuff, I guess never say never, right? Nothing wrong with a little speculation about what crazy tech we might invent in the future, even if it's a long shot. But "projecting shadows"? I dunno, man.
Here are some forms that I see the future of anti-dissent technology advancing and perfecting:
- "Mind control" tech, which leverages sophisticated and fine-grained control over media, social networks, and the flow of discourse over the internet to influence the public mind on a large scale.
- Bio-power weapons like tazers, tear gas, LRADs, etc, which use our physical reflexes (usually the pain response) to force involuntary compliance without injuring us.
Those things already exist - at least in rough form - so maybe yours are better. But I guess my point is that the future of power probably doesn't involve a higher-tech implementation of traditional modes of control (like censoring a speaker), but rather weird end-runs around the whole problem-space. Making it so that such disruptions just don't matter, because the meaningful social control is exerted elsewhere.