Well, I'm here rather than on Usenet. Overall, I think that the Threadiverse is preferable

Usenet had real spam problems for a long time.

But if you want some benefits:

• Wide range of powerful, mature clients with extensive filtering functionality, offline reading support.

• Better client-side accessibility. I mean, you can be blind and use a screenreader or something on Usenet. Going to be a lot less ideal on the Threadiverse.

• Comment editors are probably better than the in-browser textarea editors or clients with limited text-editors that I've seen (though the Threadiverse has Markdown as a standard, which I think is generally preferable). Though I haven't been browsing Usenet in some time, and maybe they have MIME-encoded Markdown or HTML or something as a common thing now.

• More-standardized support for posting embedded binaries.

• Commercial service is available. It's great that people donate their time and funds to make Threadiverse servers run, but there's something to be said for the resources available from commercial service. There's nothing stopping someone from running a commercial Threadiverse instance, but AFAIK, nobody presently is doing so.

• Newsgroups are more discoverable than are communities on the Threadiverse

you really need to use the https://lemmyverse.net/ index to find any communities out there, as otherwise you'll only see it once the exact name "!community@instancename" has been searched for on your local instance. Usenet (mostly) propagated newsgroups everywhere.

• Probably a larger userbase, though I haven't dug up current numbers. Certainly a different group and set of interests.

• Some PGP use and client support.

• I would bet that Usenet servers can scale up to more load than can Threadiverse servers.