The article pointed out that Eternal September offers free subscriptions.

I'm not sure what an "indexer" is, such that you'd need to subscribe to it; is that some kind of online service like Deja News? I used to just download everything that appeared on the handful of groups that interested me, and store it locally. Then I could do local searches.

That "store locally" capability wasn't some bag of bash scripts I cobbled together; I thought all newsreaders could do that natively.