tell that to airbus engineers. Perhaps you can boycott flying on every airbus because it says "retard" to the pilots on landing.
Do you not know that words can have more than one meaning? From the context you can tell the meaning. When airbus use "retard" they're using it to mean "to slow down".
It's not "these 6 letters in this combination is banned", it's "stop insulting people based on mental illnesses".
Then don't say/write bigotted things. Honestly, it's like asking people not to write spelling or grammar mistakes in documentation. It's not that hard.