How does dark matter clump in the first place? It does not interact with itself except by gravity. Therefore it is always in orbit with itself.

The stuff has a maximum velocity as it stays with galaxies.

Largest galaxies should have the most. The smallest none.

it may not stick together in the form of planetary accretions but if it interacts with itself then it is in orbit with itself.

The halo of a galaxy is the greatest distance of elliptical orbits around the center.

Black holes in the center of galaxies should eat up dark matter. Apparently it does not.

Perhaps there are no black holes rather only a region where dark matter is at its closest point of a approach. Dark matter can escape.

The total mass of dark matter in a galaxy is proportional to the mass of the black hole in the center of the galaxy.

There is nothing wrong with infinity as long as it is only infinite locally.