Apple Releases iOS 14.5.1, iPadOS 14.5.1, macOS 11.3.1, and watchOS 7.4.1

To what? They look the same to me.

I see left to right: red, brown, green. They used to be red, yellow, green.

You may want to color balance the monitor again. Seems the chroma or brightness has changed

Sometimes, I’ve found that after a system update, color calibration resets back to its default.

Fortunately, there is a simple fix. Open System Preferences and select Displays. Go to the Color tab. Select a profile that isn’t already selected. Then re-select the one you were using.