"Is there a noun to describe the state of a word’s capitalization?" Yes. The noun is 'case'. Upper or lower.

"Is there a noun to describe the state of a word’s capitalization?" A word can be, in ordinary text, capitalised: Queen, all lower-case: queen, all upper case (or all capitals/"all caps"): QUEEN. I suppose a noun phrase to describe this might be 'capitalisation state'. I spell 'capitalise' the British way.