Not every spell has to kill or torture to be controversial, to say the least.
Every Harry Potter fan knows the three Unforgivable Curses by heart: Cruciatus (the torture curse), Imperius (the spell that allows you to control someone else's actions), and Avada Kedavra (the killing curse).
However, fans believe that the list is not complete. In the world of Harry Potter, some spells are arguably as dangerous as the three Unforgivable Curses. But one spell that remains perfectly legal in the wizarding world, fans say, should definitely be included among the Unforgivable Curses.
According to Reddit, that spell is Obliviate. Think about it: there is a spell in the wizarding world that erases your memories forever, and it is perfectly fine to use it however you want. Gilderoy Lockhart has built his entire career on this spell, and even Golden Trio member Hermione Granger used it on her parents to protect them from Voldemort.
However, there may be a good reason why Obliviate is still good to use. It is most likely used to keep Muggles away from the wizarding world, or to make sure that a Muggle who has been exposed to magic will quickly forget it and not share the secret.
Obliviate is definitely a controversial spell, but Unforgivable Curses are called that for a reason, fans argue, saying that there's no justification for taking away someone's free will, torturing them, or killing them. Meanwhile, the memory erasing spell is sometimes used for the safety of the wizarding world, which is why it remains unlabeled.
But is it that simple to explain?
"That's worth exploring because it is certainly morally wrong to tamper with the brains of muggles like that for self-serving reasons. In Goblet of Fire, there's a paragraph in which Mr. Roberts, the muggle manager of the camping side they used during the Quidditch world cup, said "Merry Christmas" when the Weasleys, Harry and Hermione left, indicating that he was starting to feel disoriented from all the memory manipulation," Redditor dapzar noted.
Ugh, the dilemmas of living in a magical world! Makes us happy that we are but a bunch of muggles who know nothing about it... unless our memory was simply wiped out at some point, of course.