DM usually forms a halo as it orbits the center of mass of whatever it orbits (galaxy, globular cluster), and because it doesn't interact otherwise, it cannot slow down, cannot shed momentum, so it is likely mostly not a disk, but a big sphere, and probably a shell around galaxies.

That sounds a little like an additional dimension or alternative something truly “out there”. Ie maybe gravity’s force relies on some process that reverses at the macro scale.