Grayscale filters and low vision

iOS 10 contains color filters - one of which is for grayscale.  I had someone ask if grayscale filters benefit people with low vision.    Do they help people with any of the areas listed in our document such with light sensitivity, contrast sensitivity, color perception, etc.?  Or is grayscale more of a diagnostic test filter or a novelty hat doesn't actually make content easier to read for people with low vision or color perception disabilities?

Best Regards,

Jonathan