The change from red to orange was to have a color that's a blend for less colorblind people to be unable to notice. The pulsing was added on top of that for even the most severe colorblind people to be able to notice.
I'm not colorblind at all but the orange can be hard to see in some maps, but the pulsing still lets me know there's something on the ground and I should get out of it.
Short of a slider for AoE colors (which would only work for generic ones) they've done many things to accommodate colorblind people without making aoes too blatantly obvious. Things like the lines on Chirada/suparna in garuda for instance
