The argument is not new; it's from the 19th century and called Olber's Paradox.



The solution is not the dark matter, because if it absorbed all the light, it wold heat over time to 6000 F and begin to radiate itself. So the sky would still be bright white, and life on earth were impossible.

The solution is the finite age and the expansion of the universe. The farthest objects we can see are now 46 billion (not 15 billion) light years away. Light from objects outside that area can never reach us because their distance to us is growing faster than the speed of light. Only for that reason it's dark in the night.