This is misleading. He's using an app with AI image recognition that is deliberately using his camera to do this. This isn't a hidden feature on a phone to show this, "mode" off.

That's not to say that Google, Apple, and app developers aren't trying to do the same thing, or aren't capable of doing the same thing. However, it is misleading to say that every phone is doing this at all times.

For someone who has to have a smartphone, the best solution at this time is to use Linux on it, or an open source version of Android without Google services (AKA custom ROMs), remaining completely open source.