Currently, it seems Apple uses something to detect colors in app icons and make them look good in dark mode, but for apps like Subway Surfers, that doesn’t happen, and why would they change the icon? So, behold! My fix to this problem: There should be some color picker and changer in xcode to change the colors on your app icon for dark mode. This would help a lot for apps like CARROT weather where the image just doesn’t look right when it has a dark tint. This would make the app seem presentable in dark mode and light mode.
Developers should be able to change the colors on their app icon for dark mode.
Have you raised a Feedback report to suggest this? If not, please do so at https://www.apple.com/feedback/ then post the FB number here.
Developers can already set dark mode specific icons using the Xcode 16 beta as they prepare for the fall launch of iOS 18. Since iOS 18 and Xcode are still in beta, developers cannot update apps to support iOS 18 until public release this fall.
As zhrispineda mentioned, developers can create their own Dark mode and Tinted icons.
Here's a link to Design Resources including production templates for Sketch, Photoshop, and Figma for designing all three states of icons.
I'd also give the Human Interface Guidelines a few minutes of your time. It has a great section on App Icons for Apple platforms to help you through all the design considerations you'll want to make.