Covering Hair
I am saying the same thing. Head is not instructed to be covered unless it is adorned. Since it is not a private part, therefore, it doesn’t fall in the category of “guard your private parts” and thu need not be covered as a religious directive. However it is covered as a cultural norm.
What usually stays uncovered has to be determined by the culture. Hands are usually kept uncovered. To keep them covered requires unusual hardship; they can stay exposed with their adornment, unlike the head, which is not difficult to cover, and in many cultures it is not supposed to stay uncovered. However, if in some culture, it stays uncovered, it can stay uncovered with adornment.