It depends on how you define "wide color". Yes they use a color space with a wider gamut, but if you're trying to display a regular JPEG image it won't look any different.
Yep, most JPEG images might not look different, however the OS allows RGB values outside the regular range for any color specific API. When working directly with colors, the wide color support is still relevant (and for me, led to the bug I described - devices prior to iPhone 7 didn’t exhibit the bug, because the OS clamped RGB values to the standard range.).
