Is נשתנה הטבע an answer for conflicts between Torah and science?

The most common answer to contradictions between science and Torah is נשתנה הטבע. This answer appears in the Rishonim and Acharonim to explain why scientific/medical pronouncements found in the Gemara don't correspond with reality.  In fact, R' Aharon Feldman used this idea heavily in his explanantion of the ban on Slifkin's books:

There are many places in the Talmud where statements made by the Sages seem to contradict modern science. The most common are the cures and potions which the Talmud gives for various diseases. Our great halachic authorities have noted the phenomenon that these cures, in the vast majority of cases, do not seem to cure illnesses in our times. 

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The most widespread explanation offered for this is nishtanu hatevaim, “nature has changed” - cures that worked in the times of the Talmud are no longer effective.1 There are many examples of illnesses and cures, which because of environmental and nutritional differences and physical changes to the body over the years are no longer effective.

Furthermore, R' Feldman goes on to explain why we need to believe that Chazal did not make mistakes in science:

As the Leshem cited above says, if even regarding matters which are not related to halacha, the Sages say, sod Hashem liyerav, “G-d reveals the secrets of nature to those who fear him,” then certainly there must have been siyata dishmaya (Divine assistance) and even ruach hakodesh (a Divine spirit) assisting the Sages in their redaction of the Oral Law. It is therefore inconceivable, to these opinions, that G-d would have permitted falsities to have been transmitted as Torah She-be-al-peh and not have revealed His secrets to those who fear Him.

However, I believe that this is an untenable position for the following reasons.

1. There is not a shred of evidence that נשתנה הטבע. Remember, the Geonim who lived only a few hundred years after the time of the gemara already stated that the cures of Chazal don't work, that is a very short time for all of the cures to suddenly start working. Additionally, in the case of many of the Torah science conflicts it is quite implausible to say that נשתנה הטבע.

a. As I posted recently in Where does the sun go at night? the Gemara in Bava Basra (25a) states clearly that Chazal held that the Sun revolves around the Earth and that the Earth is surrounded by a roof that the sun goes out of at night. It would be preposterous to claim that in the times of Chazal the Sun revolved around the Earth and went out a window but now נשתנה הטבע and the Earth revolves around the sun etc. Everyone can understand that such a change didn't happen.

b. The gemara seems to say that lice are born from spontaneous generation. Again it is not plausible to think that in the times of Chazal there was spontaneous generation but in the last 1500 years it stopped

c. There is a fascinating site השתנות הטבעים which has a long list of things where what Chazal say doesn't fit the scientific facts of today. If you look at the list (which is only partial) you will see that it is quite large. To believe that in all of these things נשתנה הטבע is quite a stretch for anyone. Here are just some of the changes related to the human body. You would have to believe that the human body changed drastically as 

a. none of the remedies of chazal work

b. the things that Chazal say are dangerous are not (e.g. eating or cooking fish and meat together), and things that Chazal say are good for you (rotting fish) are dangerous

c. Genetics changed (it was once a good thing to marry your niece)

d. all things about birth and a baby's development changed (see 7, 8 , or 9 month pregnancies), the position of babies when born, women don't get pregnant from the first sex act, etc.

e. various halachos related to mila such as washing the baby on the third day, metzitza bpeh (which was considered to be necessary to ensure the safety of the baby).

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In fact, I don't see a single torah science conflict where it is plausible to say נשתנה הטבע.

2. If Chazal had a kabbala about science and received their science from Har Sinai or Ruach Hakodesh, you would think that they would have had a kabbala that the world is going to change and that the science would no longer be true. נשתנה הטבע should also be part of Torah. After all, if you are going to claim that all of science is in Torah then this very important fact should be there as well. Yet, Chazal never even hint that the scientific pronouncements that they are making are only temporary. They didn't say that remedy X will only work for a limited time. they made a blanket statement that remedy X cures Y. It is clear that Chazal had no idea that נשתנה הטבע was going to happen, why not? If Torah included science it should have included נשתנה הטבע as well. 

3. Based on what I said in 2 we can take this 1 step further. According to the Gemara in Shabbos, the Torah preceded the creation of the world by 2000 years and הסתכל באורייתא וברא עלמא, Hashem used the Torah as the blueprint of the world. If these scientific pronoucements are part of Torah then how can they suddenly stop working? For over 4000 years remedy X cured Y, suddenly after the era of Torah Shebaal Peh ended the world changed so this stopped working and the torah became untrue, why would Hashem do such a thing? It makes Torah into a joke. Why would Hashem change the world so that Torah no longer reflects the world if the world was created based on Torah?

4. How come the Science that Chazal got from Sinai exactly matched the Science of Chazal’s day? Isn’t that a bit strange? For example Chazal's description of the Sun revolving around the Earth and going out a window matches almost exactly the Greek view of things.

5.If nature changed, how come no one else noticed it? Why is there absolutely no record in the non-Jewish world of any of these changes?

I can understand how the Rishonim and Early Acharonim believed that נשתנה הטבע. They did not understand the world from a scientific perspective and they did not see the difficulties inherent in saying nishtanu hateva’im, in fact, it probably fit in with their world view. But to insist on saying נשתנה הטבע in 2017 is simply foolish.