I find it hard to believe that Popular Science would make such a mistake, but the author has reinforced the mistake by starting the article with “The dark side of the moon, despite its name, is a perfect vantage point for observing the universe.”
But all the quotes from scientists correctly say “far side of the moon”.
I know this isn’t really “science news” but I couldn’t find any other community to share this.
Dark side and far side of the Moon are equivalent terms.
Historically, yes. In modern science the dark side refers to the side facing away from the sun.
Which is the furthest side for us.
Only when the moon is full. When it's a new moon, the farside is in full sun.
Well yes, it waxes and it wanes, but like so many people have already said, most people know what you mean when you say "the dark side of the moon".