Fact of the matter is that these mods are not lawyers, and even if they were not liable, they would not have the means to fight this in court if someone falsely, or legitimately, claimed they were liable. They’re hobbits with day jobs.
I also mod a few large communities here, and if I’m ever in that boat, I would also jump. I have other shit to do, and I don’t have the time or energy to fight trolls like that.
If this was Reddit, I’d let all the paid admins, legal, PR, SysOps, engineers and UX folks figure it out. But this isn’t Reddit. It’s all on the hobbyist mods to figure it out. Many are not going to have the energy to put up with it.