To answer the OP original question .. No it's not drying up.
Things have certainly changed and it's become more of a challenge but Usenet is here forever as long me fellow pirates be sailing the internets and keeping things real.
I admit retention isn't as great it used to be (ah the good ol days ceratinly were very good indeed) but if you want something today grab it quick or know of a good news server outside the reach of DMCA takedowns.
Part of the problem with take down notifications is the attention nzb indexing have brought to usenet.
Before it took some work and know how to get your binaries but now it's automated and easy and on the radar screen of the MPAA/RIAA
So NZBs are sort of a blessing and a curse at the same time.
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