Has the world become less colourful? (twitter.com)

Worked in an auto parts supplier, in the painting department, and if the client/brand started a new project with a painted bumper (with a color other than white or black), our staff always hated it because the color matching with the rest of the car was always a nightmare. So maybe the quality control standards could play a role in all that.

Is it intentional irony that the poster's avatar is an image of a sculpture missing its original coloration?

It does a little every year that those outdoor Chagall murals in Chicago fade.