By whatever means science attempts to deny that consciousness exists (as they do with the concept of choice) the singular goal remains the same, that is to deny any possibility of the immaterial or more precisely the unmeasurable. The myth of science as being the sole holder and means to be truth must be upheld at all costs. There is a tremendous cost in quality of life for anyone who buys into the myth that only the material is real and everything else is an "illusion". — Rich
...and the attempt to apply scientific method to the kinds of philosophical issues that can only be properly addressed in the first person is the precise meaning of 'scientism'. — Wayfarer
I would absolutely love to start a new discussion over this at some point, but I agree and disagree with you both at the same time.
If subjective, first-person experience is a part of the world (as it does seem to be, thanks Descartes), then there are a number of courses of action that I see that science can take to account for this:
1.) Deny that first-person experience is something "special" and try to explain how it "emerges" from unconscious, third-person objectivity, as elim and reduct mats etc try to do.
2.) Deny that consciousness is fit for scientific study, as behaviorists and even some phenomenologists believe.
3.) Change the scope of the science itself to account for subjectivity.
By far, the third option seems, to me, to be the least used. Super-Scientists (as I like to call them) have the rhetoric against religion (and even philosophy!) for not observing the empirical data and for constraining the world to a hypothesis (when it should be the other way around), yet all too often they deny what is most obvious (consciousness).
So yes, I do agree that science, in particular physics and neuroscience, has an almost masturbatory fetish with reductionism. It's implausible, if not wholly insufficient.
That being said, I don't agree that scientism is merely the utilization of science for "first-person" projects. If we are being completely honest, if science can't answer questions about consciousness, then probably nothing can. Philosophy has its uses but if we expect it, and/or its relatives like mysticism or religion, to explain something when it has a generally poor track record of linear, teleological progress (not that that's inherently a bad thing), we're going to be sorely disappointed.
I also don't agree that there is a strict demarcation between science and philosophy. Science is more than just the study of third-person, objective facts about the world, and philosophy is more than just the study of first-person accounts. In order for there to be such a demarcation, there should need to be some kind of explanation as to why science can study this-and-that but not the stuff philosophy does.
I like to think myself as an open-minded methodological naturalist. When push comes to shove, I would rather align myself with the scientistic Super-Scientists rather than those who try to exclude science from some domain of inquiry (even it's justified), because all too often I've seen that those belonging to the latter group are pushing some sort of reactionary set of beliefs. "Science can't explain this!" unfortunately gets lumped together with more conservative claims like "Science as-it-exists-today is not capable to understanding this!" All too often the intentional limiting of science is an unconscious mechanism meant to curb the perceived threat of meaningless objective nihilism or what have you. Hence why phenomenology has been criticized as being conservative and trying to seclude human meaning from the rest of the world.
So once again I go back to the list I made before: that which cannot be studied scientifically must either be mistaken, unfit for scientific inquiry in general, or unfit for scientific inquiry as science is practiced today. There are examples of all three: the first includes things like ghosts, phlogiston, and magic, the second includes normative ethics, politics, theology and any sort of transcendental or supernatural-ism (and even then it could be argued that "technically" we could use science to do these things, albeit in a very clunky and indirect way), and the third includes, in my opinion, things like consciousness, aesthetics, and perhaps even some theological issues.
Like I said, I don't see any real strict demarcation between science and philosophy. You can go off and focus more on one rather than the other but they nevertheless are inherently tied. It's silly in my opinion to have a separate branch of inquiry, secluded away from everything else that studies matters in a methodological black box.