People are claiming that this paper suggests Dark Matter doesn't exist.
This isn't strictly the correct interpretation. There is evidence of dark matter (gravitationally) and in fact, there are alternate theories that show physical evidence that are ignored by mainstream physics (my friend Dr. Mills is the originator of one such theory. His data are compelling.)
What this paper's result actually says is that the candidate "quantum mechanics" based particles that have been postulated as being dark matter...are now ruled out.
Other experiments in recent years also ruled out hypothesized candidates that were compatible with the Standard Model.
The presumption of course is that the Standard Model isn't itself flawed (it is.)
From this evidence, Mills' theory actually gains more strength. His claim, backed by mathematical physics and lab results, is that dark matter is Hydrogen, in a special state. You can find some of my posts on Quora about dark Matter.
https://phys.org/news/2021-11-cosine-team-evidence-dark-damalibra.html