Ditto "pot calling the kettle black" when the reference is to the blackened exterior of a pot used over an open fire which blackens in the same way a kettle does. Both are affected equally. It's an idiom that easily conveys the silliness of accusing one of a shortcoming that is equally applicable to the critic.

While truly offensive terms/idioms should be avoided, scrubbing language of its creative and figurative originality renders it pallid and  dull. Perhaps those who cry foul about perceived bias should dig a little deeper to uncover the meaning.