The thing is that this time it's different. A revolution has to form somewhere. How will it form when every single citizen can be monitored for compliance 24/7? Everywhere you go, everyone you talk to, everything you do is tracked and analyzed. In the past, the government can't do anything to stop a revolutionary until they've become known as one. But in China they'll be able to stop revolutionaries before they become revolutionaries. At the first hint of anti-establishment sentiment someone can be instantly reeducated.

Say there's mass economic strife, and people want to revolt. Ten people suddenly get the idea to overthrow the government. They organize a get together in the woods, with no technology allowed. Facial recognition can tell the ten of them joined as a group, logs showed they all did not use any technology for a period of hours, they weren't seen in any camera or microphone database for hours... Hmm, very suspicious. An automated system can and will recognize these factors and the group will be quickly sent for reeducation.

Once the technology passes a tipping point, there's simply no way back. The technology enables the existing power structure to be maintained forever.

And that's assuming human soldiers are involved. At some point - maybe 50 or maybe 150 years from now - robotics will be advanced enough that you won't even need cooperation of soldiers, and at that point the entire population can be controlled with the push of a button.