I have not watched the dystopic thriller you mention, so I don't know what kind of drawbacks you are expecting, but I think this technology might have some useful applications.
E.g. an image-upload site could answer requests for deletion on privacy grounds not by taking the whole image down, but by obscuring only parts of the image.
Or imagine you're taking a selfie in a crowded place and don't want all those other people diverting attention away from you.
Basically, this could be used whenever someone might go for manually painting over parts of an image to remove content. Something similar for screenshots of conversations might be useful as well.