That is the nature of a "dog whistle" - it has a legitimate meaning, and some people use the legitimate meaning. That legitimacy gives malicious people plausible deniability. Social media sites cannot tell the difference, and quite often it's very hard for people to tell the difference as well. Social media sprays weed killer on all the discussions because they don't want their app covered in weeds; not having flowers is too bad, but weeds are worse (not my personal view).