Yes, but in that case there was a clear benefit to the implementor. Faster checkout = more money or at least more free time. In this case what would be an ince

Yes, but in that case there was a clear benefit to the implementor. Faster checkout = more money or at least more free time. In this case what would be an incentive for Facebook, Instagram, Snapchat & co to implement this? There would be also issues to have the badge always visible, reducing its functionality. I think this kind of change would only come if it were mandated by regulators. But in that case it could be more interesting to upload your face to some red-list database and then the sites would have to blur images where it is detected. Next step is replacement eyes and blocking à la Black Mirror.