spam murdered it.

It got ridiculous pretty quickly. The overhead to spam was so low as the protocol was designed to be low friction for posting. The system then took care of carrying the payload everywhere in a reasonable time. People fought back with filters and kill lists. But was not really enough.

Once the ISPs decided they did not want the added cost of running the servers usenet tanked pretty quick. Still alive here and there. Not even close to what it could have been or even was.

Surprised someone has not made a mastadon to usenet transfer protocol. It almost fits both projects goals.

Spam fell off drastically after Google Groups disconnected from Usenet a couple of years ago.

Binaries killed Usenet, not spam.