NSFW filtering was supposedly fixed a month ago, but it either isn't working or the instance hasn't updated to the latest changes yet.

As a workaround, I've been hiding the sections with a uBlock Origin filter.

Just add these lines to the "My filters" page in uBlock Origin. The first line hides the "Random Posts" section, and the second line hides the "Random Threads" section. (Replace "kbin.social" if you're on a different instance)

kbin.social##.section.posts
kbin.social##.section.entries

I also hide the "Active Users" and "Related Magazines" sections.

kbin.social##.active-users.section
kbin.social##.related-magazines.section.magazines