I am of the opinion that there should be more granularity to NSFW than a simple binary.
I'm a fan of how e621 does things:
rating:s (safe)
rating:q (questionable)
rating:e (explicit,)
But I would add another:
rating:t (traumatic, known elsewhere as Not Safe For Life)
Call it "purity" and allow users to filter posts to allow or block any arbitrary combination of purity levels (wallhalla, formerly wallbase, does this if you want to see how it could work).
if/when it happens, I'll be there for it (I'll bring friends too). Between now and then, I'm not holding my breath.