The colour blindness feature on Photoshop is terrible. I have been fully categorised as a deuteranope and yet the feature on Photoshop to proof images for this just does NOT work. Come on Adobe, make an effort!
There are multiple subcategories of colorblindness and color deficiency. The colorblindness proof options provided in Photoshop are for the most common types. We'd need about 30 different profiles to cover all known types. And you may be one of the less common types.
The colorblindness proof profiles are supplied and verified by some of the best known color vision researchers in the world.
But they can never be 100% accurate because they're reproducing the image on an RGB monitor intended for a color normal observer -- they cannot match the different spectral sensitivity of many color deficiencies. But the profiles do provide a very close approximation for color normal observers to see what a common color deficient observer would see.