> The TV makers don't need ACR when you are using apps on their OS. Those apps all report the currently playing title to the OS maker.
That would just tell them what show you saw. With screenshots they can see what was on the screen when you paused the show, what scenes you rewound and re-watched or fast-forwarded through etc.
For example, if you pause a movie on a scene with boobs, they can assume you like boobs. Pause a lot on screens with text, they can assume you're a slow reader (with how long you tend to pause the screen indicating how much you struggle with reading). Maybe you're the kind of person who has to go back and rewatch scenes with heavy exposition or you like to watch violence and gore frame by frame, or you skip through certain shows just to get to the songs/musical numbers. Pause/rewind a lot and it might indicate that you're busy/distracted, but also that you care enough about what you're seeing that you don't just let the content play.
Even if they already have the title of the show being played, not collecting those twice a second screenshots when they have the ability to would be leaving a ton of data on the table.