Over 40 more like. USENET was quite mature in the early 1980's.
Indecently, the decline in the popularity of USENET makes it much less useful for anonymous messages; it's much easier to conduct traffic analysis amongst relatively few users/nodes [1] than it was back in the mid-to-late 1990's when USENET was at its peak and every ISP provided a feed. These days you will stand out if you have (or request) a USENET feed. Back then, it was the norm to have one.
[1] Yes, traffic volumes have increased (primarily due to sharing binaries rather than text), but the number of active users/nodes has certainly declined.
Those flying the Jolly Rodger. Filter out the binary newsgroups (leaving only the text discussion groups) and the resulting load is a tiny fraction of that.
If you control the Usenet servers then you control what gets synchronized to your servers. If you filter out the binary groups they will never traverse your network connections to your servers.
I run a text-only Usenet server. As a sibling commenter says, you work out with your peers what you want to receive. I carry most of the text newsgroups, and according to my daily report I got about 3000 new messages yesterday totaling a bit over 9 MB.
Indecently, the decline in the popularity of USENET makes it much less useful for anonymous messages; it's much easier to conduct traffic analysis amongst relatively few users/nodes [1] than it was back in the mid-to-late 1990's when USENET was at its peak and every ISP provided a feed. These days you will stand out if you have (or request) a USENET feed. Back then, it was the norm to have one.
[1] Yes, traffic volumes have increased (primarily due to sharing binaries rather than text), but the number of active users/nodes has certainly declined.