Because some marginalized people perceive an implicit bias and veiled offensiveness in all manner of communication within those they regard as part of some sort of hegemony. If there’s a vehicle for applying restraint or discipline or humiliation, it will be exploited for reasons often vindictive or speculative.
See this guy gets it when others don't. The Radical Left has a victim mentality, always whining about systemic injustice to get what they want. When will conservatives wake up and realize that every aspect of this code of conduct is designed specifically to oppress them?