Since WoW released profanity, masked profanity, slurs, hateful speech, sexual inuendo or references, crude references, spam, advertising, etc have been against the rules.
The filter exists to protect children in particular from people who can’t follow the rules. I tis not permission to break the rules you agreed to.
No more than a bullet proof vest gives you permission to shoot someone.
Mature Language Filter (aka The Profanity Filter)
This can be activated within your Interface Options: Main menu (ESC key by default) Click Interface > Social and check - Mature Language Filter.
Once enabled, all inappropriate words in our profanity database will be filtered and masked to appear as jumbled characters, such as ‘*##@&’.
Note: The filter does not excuse the language used. The filter serves as a temporary shield, to help parents of minors and others who do not wish to see it, to block it. Our policies prohibit the use of both clear and masked inappropriate language.