Would it benefit the communities, or the public? Why should they be hidden?
As someone who is in their own niche communities (not on Lemmy) I suggest communities could have 3 modes: Standard, NSFW, and NSFL. If a community is marked NSFW or nsfl, it can never go back to Standard. If a community is marked NSFL, it can never be NSFW or Standard, or maybe if it does, all content from it is deleted.
Users could then set their preferences to standard, NSFW, or NSFL. If they choose NSFL, they see everything.
I think there needs to be individual degree of control beyond just the labels; especially for individual/small servers where owners might feel more individually liable.
For example, even within the NSFW space, there’s a wide varying degree of acceptable-ness depending where you are in the world and what your personal feelings are. A server owner in a more repressive parts of the world may put themselves in harms way if any LGBTQ+ (and apologies in advance, as I know I’m missing several letters and number, but I don’t remember the sequence order) content. Further extreme of the spectrum, “legal” age of drawn characters is another huge legality concern.
Simply having labels and depending on community moderator to label correctly (or even allowing server operators to try to override locally) seem like a only a very basic starting point, individual override is a must to prevent content that may get operators into trouble from even being shown in the first place.
The community. Right now, sometimes people post stuff and it gets down voted into oblivion before anyone who actually subscribes can see it. And then even when you go directly to the community, people don't see that post because it's down voted so much.
And I mean.. The posts in question were so not offensive.. Just probably not what the general public wants to read or engage with.
Let me give you a concrete example:
How was your church service today?
That's it. That was one of the posts that was down voted into oblivion.
I don't think it's possible currently, but maybe a feature we can suggest for the future.
As for why your post got downvoted, it seems that Lemmy is majority Atheist, based on the amount of posts I see on "All / Hot". Your community may be targeted by a small group if this is a recurring event.
I don't have a good solution for you in the meantime. I know that communities can be blocked by instances, so you may be able to get in contact with lemmy.ml, beehaw, lem.ee, etc. instance owners and ask them to block your community from their feeds, or something like that.