I’m pretty sure since this video the devs changed the color calibration between HSV and RGB
indeed they did @theluthier They changed it back to the old behavior, so RGB of (0.5, 0.5, 0.5) corresponds to a Value of 0.5 again.
But I’d need to see a screenshot of the Shader Editor or a ‘timestamp’ of the livestream where this is happening, to know if that is what is causing the difference (but I think it is a very likely candidate, while I don’t know of any other changes, that could affect the MixRGB Fac…)
And @pixelscholar like Kent already said: don’t rely on exact numbers to get the same results as in a tutorial or video, at least with shader nodes.