"For the best," Hermione scoffed. "The parents lose a child and all memory of happiness they had ever caused. Let’s say have another and end up finding out about the magical world when  that  one gets their Hogwarts letter. They live their lives with just the occasional headache and the deep sadness when they pick up their  one child from the Hogwarts express, without understanding why it feels so incomplete. But sure, as long as the magical world stays hidden, that’s good enough."