It hasn’t been widely used as a slur for disabled people for a very long time and is almost universally accepted as an alternative to “extremely stupid”. People can choose to continue being offended over it if they want but it makes a lot more sense to just let it become another generic insult if they genuinely care about nullifying its damage. All the continued performative outrage over the word from a minority of people has accomplished is turning it into a right wing clarion call.