Not to be a party pooper but this is a paid service. I am sure there are reasons to pay but I bet their archive is the same as https://usenet.blueworldhosting.com which is free. A free web frontend can be found at https://newsgrouper.org

I run newsgrouper.org as a hobby project. My architecture cannot support searching within article text, only by author, subject and/or date within one group at a time (or the set of groups you have subscribed to). Usenet-Rewind does support full-text search.

It has a free account has 25 full searches with advanced filtering etc.

Do those services have many more posts than what can be downloaded from archive.org and searched locally?

Newsgrouper is banned in UK for "safety concerns"

Newsgrouper is my site. It's not literally "banned", but after spending quite a bit of time studying the Online Safety Act and Ofcom's guidance, I concluded that it was just not practical to comply with its far-reaching requirements, and since I am in the UK I can't risk ignoring UK law.

Ah, the word used on the site is "Blocked" not "banned". Apologies.

A shame that you decided to not support your own country. Imagine how much you could have done whilst explaining this issue!

Alas, https://newsgrouper.org is not available from the UK (another casualty of the stupid OSA.)

Expensive, too. $40/month.