You're correct to say NSFW is subjective. It's dependent on 'where you work.' and is a matter of degrees.

I'm not sure that the "coming from a place of negativity" argument holds much weight. People are often "anti" (opposed to) an action that they deem as destruction.
e.g.
Anti-war
Anti-bullying

Leaving the merits of the stance to one side, I'm not sure how much people can effectively be for something if they are unwilling to take a stand against it's polar opposite. For example, if I'm for the non-aggression principle yet unwilling to act when some is being bullied (through fear of being perceived "negative"), I'm an ineffective proponent of that value. As Edmund Burke said, “The only thing necessary for the triumph of evil is for good men [and women] to do nothing.”