Particle physics is currently defined according to the Standard Model. Dark matter was proposed because it plugs many of the gaps of universal expansion in contrast to the Standard Model, but not all the gaps. It would take far greater effort to invalidate the Standard Model and all of particular physics built upon it. There is also the problem of not having any other model to replace the current one. https://en.m.wikipedia.org/wiki/Standard_Model
The expansion of the universe is observed as red shifts and these observations are numerous and largely uniform. Dark matter, on the other hand, has not been directly observed.
* https://arstechnica.com/features/2014/07/dark-matter-makes-u...
* https://arstechnica.com/science/2019/11/dark-matter-link-to-...
* https://arstechnica.com/science/2019/02/more-bad-news-for-co...
* https://arstechnica.com/science/2019/04/one-night-of-telesco...
* https://arstechnica.com/science/2017/02/a-history-of-dark-ma...
* https://arstechnica.com/science/2016/07/dark-matter-still-mi...
https://en.m.wikipedia.org/wiki/Dark_matter
Even Wikipedia says dark matter is a stop gap of gravitational models. The very next sentence, first paragraph, says experts believe dark matter exists for that reason.
> Without introducing a new form of energy, there was no way to explain how an accelerating universe could be measured.
https://en.m.wikipedia.org/wiki/Dark_energy
Dark energy is an unobserved stop gap as well. Dark energy was introduced because dark matter was not enough of a stop gap to qualify the acceleration of the expansion.
The reality is that there is just as much theoretical qualifiers for the presence of dark matter as there are unexplained phenomena in the standard model that needs dark matter as a qualifier.
The best possible answer to this nonsense is that the standard model is wrong because we don’t have the evidence to form a better model. All our evidence is limited to observations from Earth surface and low orbit. Hopefully the James Webb telescope will provide better evidence.