The problem is there's divergence from sRGB, and as yet no convergence on a new single standard. So all image content is rendered to sRGB still. Further, there's substantial inconsistency in various tools when it comes to compensation for the difference in color encoding between the image file, and the display. The technology to do this compensation is old, but it's weakly implemented on mobile outside of web browsers on the client side. And only major apps honor and preserve this color encoding metadata.
So the state with color management on mobile is approximately where color management was on the desktop about 15-20 years ago.
Apple have made good progress on this. All of their devices (iPhones, iPads and Macs, with the last iMac having a 10-bits-per-channel screen) are now capable of accurately displaying DCI-P3, and their software supports it very well [1][2].
Other companies are also expanding outside sRGB, with Samsung's new phones, the Surface Studio from Microsoft, and Razer's Blade [Pro] also supporting wide color gamuts, although the last time I checked Windows and Android didn't seem to be as color-aware as macOS and iOS.
To me seeing sRGB now feels like looking at EGA after VGA was invented; the phase where the tech is available but waiting for the content supply to catch up.
This makes the problem worse. There's 20 years of legacy sRGB images that will not display correctly on wide gamut displays without display compensation in software. iOS and Android are basically repeating all the mistakes made in color management on the desktop, by allowing opt outs by apps and not taking a holistic color management approach. And where the content is created, on the desktop, again if you're using any sort of specialized tool there is a high likelihood the color space information is being ignored or is even stripped out of the image - making it impossible to render correctly downstream.
Changing image encoding from sRGB is change for the sake of change - the vast majority of real world image content fits in sRGB.
Taking a step makes it worse than doing nothing? How would you go about it?
iOS defaults to rendering sRGB (and Apple's devices do it pretty accurately [1][2]) so nothing changes for legacy images, unless your content or code specifically asks for P3.
Xcode and the App Store also handles thinning/slicing so that wide color content is only delivered to and stored on devices that can display it. [3]
Pretty much all of the leading content creation apps support the matching and embedding of color profiles.
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> Changing image encoding from sRGB is change for the sake of change - the vast majority of real world image content fits in sRGB.
That's a terrible argument. Holding technology back for the sake of, what?
There were times when the vast majority of "real world" content and applications fit perfectly fine in 640 Kilobytes, 640×480, 256 colors, 2 audio channels and so on.
1920×1080 is still "good enough" and covers the vast majority of content so why bother with 4K?
Many people are happy with consoles yet why do PC owners resent it when a game's graphics are dumbed down?
In any case, wide color can make a considerable difference [4][5][6][7] (to be viewed on capable devices of course, but you can still see comparisons) and the cameras on the new iPads, iPhones and other devices take photos in wide color and do embed that information in the images.
So the state with color management on mobile is approximately where color management was on the desktop about 15-20 years ago.