I disagree. Words are just words and we give them meaning. Being derogatory and unkind to mentally deficient folks is ethically wrong. Using that word in a different context to communicate frustrating imo is fine.
"When you omit courtesy you're throwing sand in the gears of a machine that doesn't work too well in the first place."
~Heinlein (I'm paraphrasing.)
There's no glory in being a boor, and no shame in being courteous.
None of this is news: https://en.wikipedia.org/wiki/Etiquette#History
A fool never learns,
A man learns from his mistakes,
A wise man learns from the mistakes of others.