Yesterday I saw what I think the most vivid rainbow in my life. I don't remember ever seeing as bright one before. But then I started thinking whether it just felt that way because everything else seems to be less colourful these days.
Quick study on the subject seems to support my premise. For example the white, black and shades of grey are dominating the car markets. Same can be seen on the sales figures of the interior paints and other interior design elements.
It seems that the only trending colour is purple, which is kinda the grey of colours. The one designers choose if they are forced to choose an actual colour.
So yes, the world has become less colourful over the last few decades. Seeing something natural and colourful can therefore stand out more than it used to. While the loss of the colourful things around us might feel saddening I'm not sure if it's a bad thing if it makes us notice the colourful nature we still have left around us.