Yes indeed. both dark matter and dark energy have one thing in
common , they are both dark as in can not be seem. Human nature
stays consistent though history as dark demons has been used in the
past to explain what is not understood. In short I second Jacob's
position. Where is the beef for dark matter. Why all the smoke and
mirrors when it comes to the details for dark matter justification.
In astro physics they know what they are doing but when it is put
into print it is hard to put a finger on where the beef is as the
description is not detailed.

A moderator added a comment

Quote

and it's the dispersion (roughly speaking,
the variance) in these radial velocities that is the key measurement
for their argument that this galaxy has little or no dark matter.

End quote

To said moderator. Not sure you have the time but could you expand
on this = in a way that a layman can understand. If it takes two
pages then so be it.

[[Mod. note -- ###
Sorry, no time. But you could start with
https://en.wikipedia.org/wiki/Dark_matter
https://en.wikipedia.org/wiki/Galaxy_rotation_curve
At least the beginnings of both of these articles are non-technical.
-- jt]]