Modern theories in physics need to be tested and, if they significantly fail a test, discarded. Significant means a prediction that is different from the measurement many times the uncertainty. For example, a calculation in a theory A predicts the space ship to end up at a point which is five million km away from where the astronauts are meant to be, and if the uncertainty is only 100km, then we need to reconsider if this theory A might not pose a threat to the lives of the astronauts. A calculation in theory B might, on the other hand, place the astronauts on target (say only 50km away) and they live. Clearly, theory B is preferred over theory A.
In this sense, the dark-matter based theories (case A above) have been rigorously and robustly falsified to any high degree of standard in the physical sciences (see previous and next post). What about MOND (theory B above)? It too is a physical theory allowing predictions. It too can be ruled out.
Srikanth Togere Nagesh has put a large effort to track down and document the published falsifications of MOND. It turns out that the claimed falsifications of MOND have all been shown, in the published scientific research literature via rebuttals, to be flawed. In every case either wrong calculations were done or some essential physical process that acts within MOND and normal matter has been wrongly applied or even ignored. This is touched upon in the Addendum to post 69, and here we publish the full list of tests of MOND that claim MOND is out. As found by Srikanth, all are erroneous and have published rebuttals:
Why do so many researchers publish such sub-standard results? This is probably a sociological issue: a researcher benefits in the eyes of the “ΛCDM priests” if the researcher shows MOND to be wrong. The “ΛCDM priests” disfavour MOND, because if MOND is the valid approximation to the physical Universe, then the dark-matter based models are invalid. This would put “ΛCDM priests” out of job. A researcher who hopes (i) to get a prize, (ii) to publish in Nature, (iii) to get a raise in salary, (iv) to rise up in the career ladder, will thus like to publish anti-MOND results, and would often get away with it, if there were not brighter scientists who still upkeep the ideals and standards of research in the natural sciences.
Cases in point are the incorrect claims that MOND is ruled out published in Nature and Nature Astronomy (see items 17 and 18 and in The List of MOND-falsification claims).
Doing the work needed to write a rebuttal is costly, and so the here documented largely sub-standard “MOND-falsification” research is pulling down the entire research effort. The bright researchers cannot spend as much of their valuable time on actually advancing our understanding of nature, because they are constantly paralysed by needing to react to some new MOND-falsification claim. While it is necessary to keep testing MOND, this needs to be done at high quality.
In The Dark Matter Crisis by Moritz Haslbauer, Marcel Pawlowski and Pavel Kroupa. A listing of contents of all contributions is available here.
The Dark Matter Crisis 
This is a helpful post. While most of the falsification claims of MOND can be considered sub-standard, there are a few which were reasonable at the time, but subsequent observations invalidated the initial conclusions. This is to say, the claimed falsification was at the time good science and not obviously motivated by career goals. However, this is rather rare in my experience. Most of the claimed falsifications obviously involved rather little thought.
My view is that a falsification of MOND is possible in principle, but would look rather different to some of the claims which are obviously just designed to advance the careers of the authors. One would need a very long and detailed paper explaining the observations and why they really cannot be understood in MOND, including why subtleties like the external field effect and tides cannot explain the results. Then one has to consider what aspect of MOND is ruled out. For example, tests at high accelerations do not really test MOND because it is the same as GR. So galaxy clusters falsify MOND no more than they falsify GR. People do not go around saying that the high Newtonian dynamical mass of galaxy clusters compared to their baryonic mass rules out Newtonian gravity, so why do they apply this logic to MOND? To falsify MOND, one should ideally show that the inverse square gravity law works at low accelerations when there is no dominant external field, or some other problem is identified that can be traced back to the Milgromian gravity law. A carefully thought through falsification of MOND is thus possible in principle, but it would need to be a long and detailed paper. Of course, one could say the same about LCDM. I think it has been falsified because there are indeed many such long and detailed papers falsifying LCDM and which trace the problem to fundamental assumptions of this paradigm. I have come to this conclusion based on many different yet interlocking lines of evidence, which I detailed further in post 71 and the associated published review that I was invited to do.
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