And yet I know that I possess a subjective experience, and I suspect that you do to. Just because something does not currently lend itself to quantitative scientific study does not mean that it is not real.

(Edited) That's true, but it doesn't necessarily contradict what I said. Subjective experience is real - we all have it. Being real, it can be studied. But I strongly expect that whatever the study produces won't e.g. let us tell if a non-human is conscious (has subjective experience) except by arbitrary definitions that ultimately rely on being-similar-to-humans.

Note that much of the discussion of free will in this comments section has had nothing to do with souls or dualist free will; e.g. compatibilism has nothing to do with souls or dualism.

That's true, which is why I specified dualist free will.