Apple Watch model A2093
My watch has lost most of its color. NOT a grayscale issue. No reds show up and it appears that the contrast has taken on a life of it’s own.
That's a series 5 Watch. It was discontinued in SEP 2020. It sounds like it's on its last legs.
M1 Mac mini, macOS 14.3.1; Watch, series 7 GPS/cellular, watchOS 10.3.1; iPhone 12 Pro, iOS 17.3.1; TV 4th Gen, tvOS 17.3; HomePods, audioOS 17.3 and Airport Express w/ Airplay 2