Gravity does have a LS. Wikipedia should include black holes as a source of neutrinos. Dark matter may be 5 times more abundant than our normal baryonic matter, but its gravity could be more or less abundant than just 5 times more gravitational influence, but I am not sure.

My take on dark matter is that it appeared after the matter-antimatter annihilation when a billionth more regular matter was left unannihilated. Energetic radiation was the largest byproduct of the annihilation, but a certain amount of residue that still had aspects of matter with gravity was probably produced. It does not have any electromagnetic trace of light and does not seem to interact even with itself except by gravity. We have invented 3 possible particles that could be dark matter like axions, wimps or, other strange unseen mass.

The sheer abundance of dark matter is what forms the filaments of the cosmos by attracting galaxies into chains and nodules.

The other biggest mystery is dark energy or the acceleration of the expanding universe, or cosmological constant or the production of more spacetime. Black holes are increasing in number so I presume Black holes produce more Space in a transformation of matter into space under the most powerful forces in the universe. Beyond that I got 'nuttin'.