@popey @milan sure, you don't have to make it red. It could be grey for instance. Or desaturated version of the GTK theme's color.
I think the value here is to give a visual signal that free software is better. You don't need to mark proprietary software as 'red' or dangerous, but you can visually promote better choices.
So 'fix' is perhaps wrong. But, I think the visualization can be improved.