I still use Forte Agent to access a couple of newsgroups that I've visited regularly for years. They're both dying a slow death and what little traffic there is consists largely of spam and trolls. I have no idea if alt.binaries.sounds.mp3.bootlegs is still active. What sort of bootlegs are you looking for? There are still a few sites available where you can download for free live music bootlegs that are allowed by the artists, e.g. dimeadozen, etree.org. Some require an invite to join. I know for sure that dime is still very active with tons of stuff posted every day in all sorts of different genres.
My experience was the same. ISPs have dropped newsgroups, as the bandwidth was large from the few customers who used them. Usenet, I am afraid, is a remnant of the Internet of earlier decades. People have moved on to various fora: Facebook (ugh!), Reddit, tumblr, and such.
20 years ago I was using Forte’ Agent, (the paid one). I loved it but since then, the newsgroups have gone downhill and there didn’t seem to be much in the way of posts. Many of the newsgroups had nothing in them. Verizon FIOS dropped all their newsgroups so I got out of it. You will probably have to go to one of the pay to play news providers which can run you $19-29.00 USD a month. I found it wasn’t worth the time or effort any longer. good luck though.
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