This is a political design. The use or lack of colour helps extenuate the point the creator wants to create. The use of flowers, as a severe contrast to violence and war, also shows the message of peace, not war. Powerful visuals in a simple way.
Vibrant Oil Paintings of Scottish Landscapes by Scott Naismith The texture of this really grabs me but the tones of the color leave a lasting resonance that is very relateable yet exaggerated of natural sky tones.