To expand on this a little, there are tonnes of options for spying on people but the key is tying your face to your identity. If you have a phone with you at a protest and they capture your IMSI (unique identifier for that handset) they can place you at the scene. They then only have to narrow down a little which face is tied to that phone and they know who you are. If they have a way of making a large database of faces and names, for example requiring ID and facial scans to access porn, then they can make this process much more rapid. It’s almost like there is some sort of overarching plan here, some sort of seizing of power through multiple fronts which are all connected and share interests, like how people who are all rich share the interest of further concentrating power in their own hands, just as an unrelated example.