How do you not understand?
We know 2+2=4. We do not know that dark matter exists.
We know 2+2=4. We do not know that dark matter exists.
Which is why we really like telling stories about it.
My point is, we tell stories about literally everything, so i don't know what point you are trying to make.
If your criticism applies equally to basic facts, it is a bad criticism.
Pop science cosmology presentations never, ever mention these contradictions. But it is, exactly, embracing contradictions like these that would make it science, not religion. Presentations without them actively mislead the public as to what science is and is for.
Trotting out details found (or made) consistent with DM amounts to indulging confirmation bias. An honest presentation describes the current favored theory, which summarizes a collection of observations, and then whatever is inconsistent with it. Sweeping inconsistent facts under the rug is the opposite of science.
Every substantial advance has come from embracing contradictions of current favored theories. Young people are inspired not by sweeping, broad-brush stories of how the universe is, but by mysteries that remind us how much is left to be discovered.
Biologists understand this. It is very easy to get a biologist to say "nobody knows". Every non-moribund field revels in what is still wholly unknown. Only cosmology circles the wagons against contradictory evidence.
> Biologists understand this. It is very easy to get a biologist to say "nobody knows"
Depends on what you ask them about.