Could you please, *please*, try to refrain from using not-new-user-friendly slang like "tag" when you mean the CW system, or image hiding?
I've run across nsfw and porn that is clearly using the hashtags "nsfw" and "porn" but not a CW or hidden image. So they're probably trying to comply with the spirit of the rules, just are unfamiliar with informal slang.
If you mean CW, say CW. If you mean mark media as sensitive, say mark media as sensitive.