The thing about dark matter is that it seems to be highly non-interactive. If it could interact it would be able to shed its momentum through collisions like n

The thing about dark matter is that it seems to be highly non-interactive. If it could interact it would be able to shed its momentum through collisions like normal matter, and thus fall towards the center of the galaxy and clump like normal matter. Instead the gravitational evidence, like galaxy rotation curves, indicates that the dark matter is spread out in a huge diffuse halo around the galaxies, several times the radius of the visible galaxy. Thus in the same way, dark matter would be unable to form a "dark accretion disk" around a black hole, where it could shed it's momentum in order to lose enough orbital velocity to fall into the black hole. Thus the only dark matter that would enter would be that captured during formation and that which hits it directly like a meteor, so the ratio would be significantly lower. This of course assumes dark matter is a particle (or several), which is the current leading hypothesis but it's by no means settled yet. At least that's my understanding.