Dark matter has been a tricky subject to broach over the past few decades, and according to the video above, some have taken to calling it "bunk science", but Sabine Hossenfelder does clarify that the original idea for dark matter was decent in order to explain the huge amount of data being detected that couldn't be explained by anything else at the time.
However, as technology improved and telescopes became more precise, the data that they gathered also increased in precision, and when juxtaposed with the theory of dark matter, it just didn't fit. So proponents of dark matter tried to make the theory fit the data but that reduced its explanatory power.
Now, there are two competing models of cosmology, dark matter and modified gravity. And although there are cases in which one model is preferred over the other, modified gravity seems to fit the data better and dark matter has become too complicated that it makes it difficult to get at a good conclusion with it.
In any case, the video above is a fun watch. It gives an overview of the theory of dark matter, and explores the progress of the theory over the years, and why it has received more criticism in recent times.
(Video credit: Sabine Hossenfelder/Youtube)