There doesn't seem to be much of a perceptual difference from Cobalt Blue. [1]

The significance is mainly due to better durability [2]:

> the increased UV absorbance and stability in outdoor weathering and heat buildup tests demonstrate that YInMn blue is superior to Cobalt Blue

[1] https://www.sciencedirect.com/science/article/abs/pii/S01437...

[2] https://chemistry.oregonstate.edu/content/story-yinmn-blue