They don’t, this person is wrong.

I did not mean the dark side.

We can all see the dark side every month. That’s what new moon is. It’s the far side we can never see from Earth, since the moon is tidally locked. I think only a couple dozen Apollo astronauts have seen the far side with their own eyes.

the dark side is the side that doesnt get hit by the sun. That’s the only difference there.