Because that's what HDR web content is.
HDR movies playing on a livingroom TV? Sure, nothing against that. I mean it's stupid that it tries to achieve some kind of absolute brightness, but in principle, some form of "brighter than SDR FFF" could make sense there. But for web content, surrounded by an SDR GUI?
I don't know why you're asking me about examples that violate the rules I proposed. No I don't want that.
And obviously boosting the brightness of a screen capture is bad. It would look bad in SDR too. I don't know why you're even bringing it up. I am aware that HDR can be done wrong...
But for HDR videos where the HDR actually makes sense, yeah it's fine for highlights in the video to be a little brighter than the GUI around them, or for tiny little blips to be significantly brighter. Not enough to make it look gray like the misbehavior you linked.
Other than the exaggerated 10x, I don't understand how it violates the rules you proposed. You proposed a scheme where part of the screen should be allowed to be significantly brighter than the surrounding SDR GUI's FFF. That makes the surrounding GUI look grey.
> And obviously boosting the brightness of a screen capture is bad. It would look bad in SDR too. I don't know why you're even bringing it up.
I'm bringing it up because that's how HDR looks on the web. Most web content isn't made by professional movie studios.
The example video I linked conforms with your suggested rules, FWIW: most of the image is near black, only a relatively smart part of it is white. The average brightness probably isn't over SDR FFF. Yet it still hurts.
