These are going to be very popular for intercepting images on their way to a display. Think of the advertising possibilities. Ad attribution can be 'vastly improved' when both the ad and every step in the funnel are all spymarked and all of them are reliably reported on by virtue of their pixels hitting your screen.

First the low-end laptops and phones (and probably later, most of them) will incorporate some low-level driver that is constantly scanning for these and passing them to a helper app to phone home. I assume this is something Apple will, to their credit, refuse to do[1] but I don't think other OEMs will have any qualms based on what they already do with their TVs.

[1] (though they don't do this kind of thing out of altruism, but because their cash cow is app store rents and fat hardware margins, not third-party advertising.)