It is mass surveillance. It's just not being looked at by anyone until you are targeted by the government. If you are targeted, your entire life is within keystrokes of the authorities. This is the same thing the article is saying.

The article is making the point that it's not feasible to spy on every person to monitor them for wrongdoing currently. It doesn't scale and it's not cost effective. With AI that will change because it can be automated. The AI can listen to voice, monitor video cameras, and read text to discern a level of intent.