I love the Sinebow! It's a natural solution to a problem nobody ever talks about - the colors made by combining two primaries are unnaturally bright compared to a single primary. The way our monitors work, those colors emit twice as many photons. That's OK for yellow because we expect it to be bright, but magenta and cyan just look too garish.
It is discussed at the end of the sinebow article:
https://basecase.org/env/on-rainbows