That’s a fair point. I have never seen it done from a video before specifically, but I am positive that it is a technique which is theoretically possible given that there is enough data in the image. Obviously if the image was grainy to begin with then it doesn’t matter what you do to it, you won’t get anything better than the original. And regardless of how the file is exported, as long as you can take a screenshot of the video afterwards and there is enough definition in the image I don’t see how this technique couldn’t be applied.
Edit: and to be clear, I don’t know what specific transformation(s) are traditionally used in video editing. For all I know it could be a long list of transformations that are all coded to happen with the click of a button to make it more difficult to unblur. But even that isn’t entirely safe. There is just literally no reason to not use a black box/elipse or whatever in cases where the data is actually sensitive.
As someone that has used ad blockers for just about as long as I have been able to, I would like to think that this is true. However, I’m not entirely sure that it is. I’ve heard that a surprising percentage of people just don’t even know that ad blockers exist. If that’s the case then they may be very well aware of what is happening. (Using made up numbers for the sake of argument since I don’t have real numbers) Like if only 5% of users use ad blockers and doubling the number of ads they show only brings that to 10% then it is certainly worth it financially. I doubt that if you were to graph that curve it would be linear - there is certainly a point where you inundate users with so many ads that even non-technical people will start learning about ad blockers. Regardless of what the real numbers are, I would be very surprised if they are making decisions this big without at least being aware of what those numbers might be. And if they can make a small amount of money indefinitely but they have evidence to suggest that they can make even more money also indefinitely then the financial motivation is obvious. Not all infinities are the same size.