> Screen protectors also degrade light output

So does this function from Samsung. You can see in all the video demonstrations that the 'privacy' pixels are notably dimmer even head-on compared to normal pixels.

Not the same thing.

These pixels are dimmer by themselfs. They dont get muted by a layer on top of them.

This means way less energy usage therefore longer lasting battery at similar brightness!

Also these pixels can just go bright the moment you dont need this anymore, instantly making everything look good and bright again :)

This also degrades light output off angle. If you're showing someone a picture, you lose up to 50% of light output.

Sure, but presumably you wouldn't have the feature activated when you're showing someone something on your phone?