>Dark Matter and dark energy are hypothetical forms of matter and energy that we assume must exist to make the universe function the way it is.

Similar to the old concept of 'phlogiston'

When early scientists created a reaction that gave off invisible CO2 (like the baking soda and vinegar volcano of our childhoods) they couldn't figure out why the resultant material weighed less than the inputs. So they formulated a working theory that there was an invisible substance called phlogiston that had negative mass, and it allowed them to continue quantitative experiments while using that as a placeholder.

I look at the concepts you outlined the same way. We don't know what they are, we can only describe some of their properties. When a new breakthrough comes along that properly accounts for them the way the discovery of CO2 accounted for mass loss in chemical reactions, the theory will rectify and we'll move forward.

But skeptics then, as now, like to point out these failures as a failure of science - but the truth is these are just placeholders for science to stick a working model until they can understand what's in the black box.