I have no idea how to parse this comment. Calling someone a "spastic" seems horrible. Kids in schoolyards looking to score points at the expense of the disabled are horrible. Assuming that a kid with ADHD is the victim of bad parenting seems like a terrible idea. Following your idea to its logical conclusion, it seems like we'd still be calling black people the n-word; after all, much of the use of that word in the first half of the 20th century was probably intended to be neutral.