I have yet to be threatened for setting it on in 3 different subreddits with over 1million subs each. I'm pretty sure they don't have a simple way to log when a subreddit was changed from sfw to nsfw so they really don't know which subs have done it as protest vs which were like that before. It's only the top50 subscriber subs that seem to be getting any attention and it's because media and userbases are making shitloads of noise to alert the admins to it.
I expect they'll do some database queries or w/e eventually but they don't seem to know who to go threaten yet.
They're definitely threatening the big dogs first, over time they'll come for the smaller subreddits, though 1 million subscriber subreddits probably aren't as important as the defaults.