Can someone please answer how dark matter theory resolves/eliminates these two possible problems
Dark matter, per my understanding, due to gravity, keeps moving, and due to its non-interactive nature, does not stick to itself or normal matter. Therefore, it is in continuous (and may be somewhat random) movement. Wouldn't this make the speed curve of spiral galaxies pretty unstable, or unpredictable?
Dark matter, due to gravity, keeps moving, (usually most dense at the center of the galaxy). Whenever some of it enters the event horizon of the central black hole, it should not be able to come out ever again. Over million/billions of years, all of it, little by little, should eventually end up inside the central black hole, making it impossible to maintain the uniform speed curve. Even though it is non-interactive, is it correct that it still could not escape the event horizon? If so, how it is still possible to maintain the uniform speed curve of galaxies for billions of years?
I am thinking due to non-interactive, non-sticking nature, movement/rotation of dark matter should not be uniform, and it should be crossing in and out passing the central black hole, thereby some of it being consumed for ever. Once this process starts, the central black hole would begin to become heavier making the process even faster.
Also, I am thinking that to cause uniform speed curve, dark matter has to be distributed over the galaxy in certain way. All or most of it in the central black hole would not support the uniform speed curve.
Do the dark matter simulations take these two problems into account? How they are resolved/avoided?