So, this has actually been one of those things often claimed, you may have heard of it or maybe even thought it yourself (I certainly had the thought as an edgy teen). Stuff like "For all the horrors, they probably did make some progress with experiments in concentration camps" or similar things.
Now, beside the point of it being unacceptable to do so ethically - the stuff done there was also quite useless. I currently can't do the work of searching for and gathering all the sources again, but to my memory: the cruelty and dismissal of humanity made the "results" of those "studies" mostly useless garbage, saying nothing at all worthwhile for science, and being clearly tainted ideologically.
Because, while you may think that in some "ideal" world, you could have neutral research on unwilling humans, the reality has always been, that the conditions needed to get humans to do such experiments on other humans, necessitate the kind of ideological distortions, that mostly make the results useless in the end. There's simply not enough psychopaths that are also willing to do proper, frustrating, hard-work-necessitating, non-self-aggrandising research - and to get non-psychopaths to do it, you need an ideology that ultimately removes their neutrality and the neutrality of the research.
The only things I remember being deemed "useful" and "properly" done from a scientific perspective in the recovered "studies" were things like "lethality of grenades by proximity to the explosion" - something that is questionable to begin with in value and that can also be determined with sensors of different kinds - as well as "effects of massive hypothermia and frostbites" - which as far as I remember basically just confirmed what has been estimated from case studies in a broader way, as well as animal studies (the latter, admittedly, have their own legitimate controversy).
