I'm on FB daily, and my wall is covered in 2A stuff. I also see the NRA, SAF, Gun Owners, and a whole slew of other gun-related stuff in my feed. I share or repost gun-related stuff on an almost-daily basis. If they're shutting stuff down, I don't know what it is, or why.
I'm a lawyer, but I'm not your lawyer. If you need some honest-to-goodness legal advice, go buy some.