Obligatory link to Aether as the modern, decentralized Usenet. I highly suggest everyone looking at this post download the app and join some tech rooms. Just repost links and help build the community up, quite literally "for science".
It also looks like there is a blacklist for Aether (https://static.getaether.net/Badlist/Latest/badlist.json). If you're concerned about using this application because someone might post illegal content, this could be used to prevent that from being a problem. (I'm not a lawyer though. There may still be legal risk in running software like this.)