I have been doing this sort of limited color palette for years now, it makes choosing fabrics and coordinating my clothing incredibly easy. (blog.colettehq.com)
Even with a more limited color palette and tools, the app looks so much more natural. (imore.com)
Dynamic Badges will pull a color from the app's notification or pull an image from the notification, such as the profile pic of someone who messages you, allowing them to stand out against most icons, especially if you're using icon packs with limited color palettes. (androidcentral.com)