Is the Night Sky Dark in an Expanding Universe?

An infinite universe and a non infinite universe both can give you dark night skies. The question of whether the night sky is dark can't tell us whether the universe is infinite, because infinity is also complicated. And so does this answer help us answer the question about the universe being infinite or no, because it can be infinite. So yet. What does that mean? It means the night sky actually is kind of bright, but just in wave lengths we cannot see.