Dark matter is a hypothetical form of matter that is thought
to account for approximately 85% of the matter in the universe,
and about a quarter of its total energy density.
(...)
Its presence is implied in a variety of astrophysical
observations, including gravitational effects that
cannot be explained unless more matter is present
than can be seen.
Also, since it will inevitably come up as it always does in threads about dark matter or dark energy , here is an article[1] and related[2] HN thread arguing the theoretical justifications behind the existence of dark matter, what is known or can be inferred about its properties and why chances are no one missed whatever simple solution you can think of, like "maybe it's just normal matter but they can't see it because it's far away" or "maybe it's just black holes" and why it's also not entirely hubris or ignorance on the part of the scientific community.
The article you link there does not mention the SISSA discovery of 2016 [1]. In particular in mini-spiral galaxies there seems to be an unexpected, and inexplicable, interaction between dark and visible matter. This falsifies the primary prediction put forth in that medium article. And in general this issue is one that poses a critical problem for dark matter largely because it cannot just be massaged into the model.
And that last point is really the problem with model based physics. They are really really hard to falsify which can provide certainty through inertia. For instance take the heliocentric vs geocentric earth. The geocentric view (that the Earth was the center upon which everything rotated) was based upon a model. It started out fairly simple and intuitive. But then we kept coming upon ever more issues. For instance if everything else rotates around Earth then that must mean other planets travel in sort of 'swirly' type patterns that we see nowhere else in physics. Well, okay - why not. Hmm it also turns out that some planets, such as Mercury, need to just magically stop in their orbit and start going backwards at some point. Again, it's a model that we can't really falsify so okay - why not.
And it absorbs really bizarre observation after another. The only way to refute it was ultimately to be able to see 'through the eyes of god' that geocentricism was wrong. This was not hubris or ignorance on part of the scientific community. It was inertia. Hundreds of years scientific study was built upon the assumption of a geocentric Earth. Astrology was a scholarly pursuit, at least as reputable as psychology is today, developed over centuries. And it was 100% dependent upon the geocentric model. We've rewritten history to blame geocentricism on the church alone, but there was far more in play there. Going against the geocentric model meant having the arrogance to call numerous well reputed fields completely wrong, to completely discredit and repudiate the work of the most brilliant minds of the times, and to basically say you somehow know better than hundreds of years of work and pretty much everybody else.
No, it's certainly not hubris that drives inertia. It's the lack thereof. Einstein's theory of relativity sounds absolutely insane. It took the sort of man who would go on to condescendingly mock quantum entanglement as "spooky action at a distance" to have the sort of ego and self confidence, bordering on hubris, to be able to not only consider such possibilities but to spend years of countless effort refining and developing it. Much of this done when he, unable to find a professorial position, was working in a patent office - no less! Indeed if we have any bias in play, I'd expect it's rather a contagion of humility driven by the exponential growth in complexity.
If anything, the arrogance would come in the form of an aggressive disregard for alternatives. See the practically militant response to things such as MOND [2] hypotheses. It still suffers many problems, as does dark matter, but remains a viable alternative hypothesis which remains rather unexplored. Of course there is a practical issue there. Since nobody expects things such as MOND to be correct, which it probably is not, then spending years proving that is effectively wasted. By contrast as most people expect dark matter to be correct, proving it right or wrong would be an achievement worthy of a trip to Stockholm. It means pursuing MOND (or other alternatives) is a very difficult choice, in terms of career progression and prospects. Scientific inertia is a problem with no clear solution.
[0]https://en.wikipedia.org/wiki/Dark_matter
[1]https://medium.com/starts-with-a-bang/this-is-the-real-reaso...
[2]https://news.ycombinator.com/item?id=18207276