10-bits is about UHD HDR I believe. In other words, it's about how changes in video have caught up and exceeded photography and print. And rather than not being able to see 1 billion colors being a downside, this is in fact it's desirable claim: it's got lower quantization noise so you don't get banding the new gen of super bright HDR capable imaging. Take a look at all the talk about Apple's new Pro XDR Display to see where this all is going. When you do, you'll see the effect UHD TV standards are having. Roger mentioned BT2020 gamut a while ago. It's in the context of that aspiration in which Display P3 can be seen as significant, because the jump to BT2020 is too far. Even if displays that can do it become readily available, the legacy of sRGB is gonna intrude. Over at DCal forums Display P3 is known as sRGB-2020. I see it basically getting a reasonable step up in gamut while not blowing the legacy out of the water, thanks to a better balanced expansion of the primaries than Adobe RGB, and a backwards looking sRGB TRC. But video is the future and it's changing fast the way DTP stuff was changing 20 years ago!