I find it more likely that we just don't understand the real mechanisms behind galaxy rotation and universe expansion and so we just made up unfalsifiable stopgaps to make the numbers work out.
I also get the impression that while dark matter is popularly accepted as "actually existing", that is much less the case for dark energy.
Dark energy is an unrelated concept with a similar name, and there is not really evidence for it; it is speculated because the equations of general relativity imply the need for an additional term to justify the inflation of the universe, but it's not at all clear what this term corresponds to in terms of matter.
Until someone rules out stuff like using the full nonlinear Einstein equations vs Friedmann equations, or that the presumption of homogeneity/isotropy is wrong, (there's more stuff here that hasn't quite been excluded by observation) then the best we can say is that "We need some extra matter called dark matter for the standard cosmological model to work"
Maybe that is what is meant when a physicist says dark matter, and its the media that mysticizes it.
Cosmology today is, in general, very sophisticated. I mean no offense but armchair contrarian takes here are very much just coming from a place of ignorance. Any criticism we can imagine as lay people has already been plumbed to a depth and detail we will never be capable of in our lives. One can point out that there's always some degree of uncertainty in absolute terms, but I think the appropriate understanding is Bayesian, and I'd sooner bet on getting hit in the head by an astroid walking through my neighborhood than that cosmologists have this all fundamentally wrong.
The wikipedia page does a reasonably good job of going through the multiple independent lines of evidence we have for dark matter. Sean Carrol has some great posts / videos in this topic area as well. The reason we're so confident of the current state of knowledge is not somehow that physicists and cosmologists suffer from hubris that blinds them to sophomoric criticisms, though sadly there's a number of people who continue to grind that grift.