While I have seen explanations of how randomness might lead to the illusion of free will, I have not seen any line of reasoning that explains free will itself a

While I have seen explanations of how randomness might lead to the illusion of free will, I have not seen any line of reasoning that explains free will itself as being dependent on randomness (because I have not seen any explanation of free will, period.) My guess is that randomness is imagined to have a role in free will only because it is the alternative to strict determinism (which is, as you point out, completely antithetical to free will) rather than because it is clear that randomness does, in fact, enable free will. It certainly feels to me that I have free will, but the older I get, the less sure I am that I actually do. Consequently, I have no idea how I came to write this post.