There is a big difference between mild NSFW and full on porno. Suppose there is a News story with photo/video but it's a little bit graphic or violent. Nobody is jacking off to that. Maybe shouldn't view it at work, but in the library is fine.
Maybe it's a funny meme pic but there's a nip slip situation going on. No biggy; it should probably be tagged NSFW. Probably don't want it showing up at actual work. But I want to enable this kind of content away from work without a bunch of actual porn showing up in my feed.
There should be a porn tag. It's not the same as NSFW.
EDIT: The two main devs have done some amazing work here, but as I understand it they are totally booked for the foreseeable future. My rust chops aren't quite up to snuff (yet) and my frontend chops are non-existent, so it might be a quite while before I'm up to speed enough to make a meaningful contribution. In the meantime just thought I'd point out the issue.
Full fledged tagging system would be cool and help with discoverability as well as filtering.
So maybe a tag system where each tag also has a type. E.g. NSFW, flair, category, where each type have multiple possible tags. Also maybe some tags can be set by the poster and some can be set by mods or maybe they could even be set by the users where the top-n most chosen are visible on the post.