I looked at the paper, and wouldn't really call cividis an iteration of viridis. It's more of a conversion of viridis to "CVD colorspace" (can you say that?), with a few tweaks applied.
Well, from my CVD point of view it looks like one ;). It's largely the same except with better color contrast and ability to distinguish detail. But I understand it actually is missing a significant chunk of green hues for the non-colorblind.
