While I'd still argue that the hypothermia experiments are seriously flawed at best, there apparently is an argument to be made that some useful information was received from them as Robert Pozos in the scientific community argues in his article "Accidental Hypothermia" (with a rebuttal from Robert L. Berger in his article Nazi Science — The Dachau Hypothermia Experiments.

Anyways, I think in order to answer your question, there are two levels of discourse / discussion that need to be differentiated with the first one being academia / medical science.Shortly after the war was over, first reports appeared on the Nazi medical experiments, especially after the start of the Doctor's Trial as the first subsequent Nuremberg Trial in front of the American Nuremberg Military Tribunal (NMT). Knowledge had been already spread during the proceedings of the International Military Tribunal (IMT) against the main war criminals and the world was incredibly shocked at what emerged. The idea of doctors experimenting cruelly on patients, the people they had sworn to heal and protect, was a shocking reveal to the world (and later played at least part in the development of modern medical ethics).

Together with the shock about the horrid treatment these doctors dished out to their patients, it also became apparent that most of the results they produced were either a.) unusable due to an ideologically flawed experimental design (e.g. Mengele's twin research, Heißmeyer's TB research, the sterilization experiments) or b.) the corresponding documents had been destroyed.

However, the Allies did decide to investigate if there was anything useful to be gained from these experiments and one of their investigators and key medical advisors for the Nuremberg Trials, Leo Alexander, an Austrian-Jewish born neurologist and psychiatrist, wrote a report on the Rascher experiments in Dachau, i.e. the Cold Water and High Altitude Experiments. You can find the full report here. Alexander's report contained Rascher's report to Himmler about the experiments as well as his own findings about the validity of the research and the Rascher experiments.

Alexander originally concluded that the experiments had produced viable research. Alexander retracted this later in Medical Science under Dictatorship, p. 43 where he states:

The results [of Rascher's study] like so many obtained in the Nazi research program are not dependable. In his report, Rascher stated that it took fifty.three to a hundred minutes to kill a human being immersed in ice-water -- a time closely in agreement with the known survival period in the North Sea. Inspections of his own experimental records and statements made to me by his close associates show that it actually took from eighty-six minutes to five to six hours to kill an undressed person in such a manner, whereas a man in full aviator's dress took six or seven hours to kill. Obviously, Rascher dressed up his findings to forestall criticism, although any scientific man should have known that during actual exposure many other factors, including greater convection of heat due to motion of water, would affect the time of survival.

However, there were debates within academia and the medical sciences that the data produced was indeed useful. It comes and goes in waves from what I can tell but the origin of it is certainly the Alexander report and its publication of the Rascher report.

When it comes to the public perception outside of academy and the medical sciences (and I assume that was where your question was going), things are more complicated. Here again, the doctors' trial and the shocking impact it had on the world is a starting point of sorts. Mengele who had escaped as well as the other doctors experimenting on humans were regarded as so monstrous, they quickly developed into a pop-culture trope. Almost immediately after the war, the character of the Nazi doctor starts appearing in movies as a favorite antagonist. One of the most famous examples is probably "The Stranger" (1946) about the hunt for a Nazi criminal who escaped to the US in which Orson Wells plays the Nazi criminal. Albeit it is never explicitly stated that he was a Nazi doctor, it is hinted at heavily.

The trope really took off however in the 1970s when there was a sort of mania about Mengele and the other Nazi doctors. In part because of the Eichmann trial and the rumors and half-information about Nazis in South America, in part because the popularity of Italian Nazi Exploitation moves, the Nazi doctor antagonist appeared once again. And not just in Italian exploitation like Ilse or Love Camp 7 but also in big Hollywood productions. The Boys from Brazil and Marathon Man being the most pertinent examples. And thus, the Nazi doctor once again entered the public conscience.

It is hard to pinpoint but the mix of the image of the ruthless Nazi doctor and the limited information in the academic debates about the use of the data from Nazi experiments got picked up a number of popular publications and a segment of especially internet crowds (the phenomenon is imo heavily overrepresented on reddit) that have a certain perception on science. Recent times have seen a change of public perception of science, with it being a sort of cure all, make all better tool. With science become a point of contention in public debate, the idea that if ethics were chugged out of the window (ethics here often being conflated with morals or even religiously motivates morals), we'd be on Mars right now (forgive the hyperbole here) has become a somewhat popular trope in certain circles of discussion. In the matrix of this argument, the idea of the Nazis being evil but producing good science or not being evil because they produced science has gained a lot of traction.

This relatively recent phenomenon which originated in a mix of public fascination with Nazis in general, ruthless Nazi doctors, and bits and pieces of an academic debate about the uses of Nazi medical experiments from a standpoint of medical ethics and scientific rigor combined into this powerful stereotype that seems so prevalent in certain demographics.

A lot of research is still to be done on this aspect of public perception of the past but the gist of it is, the use of the trope of good Nazi science outside of revisionist circles is a relatively recent phenomenon (I could not find anything in non-medical publications before the 90s and most of it is from recent years, whether it is from publications such as Slate or Listverse articles) and one that is in my opinion rather concerning.