I have exactly the same problem. It's not just a different color tone due to different screen. I know because I took a screenshot and viewed it on my Mac screen next to the original design drawing of the icon. It has definitely been converted from .p3 colorspace into sRGB.

I sent the demo app to Apple as a bug report. It would help if other people who are having this problem would also file bug reports. I recommend sending a similar demo app to ensure that Apple developer support understands that this isn’t just a problem due to different screens displaying colors with a different tint.