Junia didn't necessarily like the use of 'dark' to describe magic that harmed because there were plenty of dark things that were good! Like the night sky when you could see the stars, her favorite dark blue dress with the puffy sleeves, and a particularly sparkly dark purple polish she liked to put on her nails sometimes. Dark didn't have to mean bad so they should really think of using a different name to describe the subject matter.

"Even though dark arts can be scary because they're used to hurt or control for bad reasons, I think it's good, in a way, that people learn about them because then we can defend ourselves against the spells and potions as best we can!" So all the people who suffered before them did teach them something. Or well, at least teach the ones smart enough to learn from them.