>>5338098I think it's a matter of visual clarity. Softer shaping and coloured-in outlines are quite common nowadays, resulting in less contrasting colours, in addition to the evident lowered saturation. There's also a visible abundance of white glowiness along the edges that's much more apparent on the bottom one.
The outlines and shading in the above image are much harsher, a strict black. Contrasting the bright colours and background. I reckon that thus communicates a clearer priority of design elements, more aptly displaying the forms and sharp edges.