This model has been in testing for 3 years and it passed all tests so far.
It already past sevral test and it solves a lot of problems that require dark energy or matter. And problems introduced by the James Webb telescope. It also confirmed cosmic chronometer findings on the expansion history.
It does not disprove models, it just shows that dark matter and energy are not needed and explains why we can’t find them.
In reality I’d call it an elegant deduction - so many different phenomena point to there being more matter than we can see, so the straightforward conclusion is that there must be matter which interacts very weakly or not at all with electromagnetic forces.
The theory works out well, the solution is not hand waving and also rather elegant.
The matter exists, I swear! She just goes to another school of thought. We communicate spookily over long distances.
When I close my eyes, I can no longer see the horse. Ergo the horse has stopped existing.