Even the effect on detecting crimes is significant. People are mistaken in thinking that the NSA needs to filter off so much noise that it is like finding a needle in a haystack, in reality filtering off noise is trivial. I highly suggest reading the following paper from 2009: https://www.blackhat.com/presentations/bh-usa-09/TOPLETZ/BHUSA09-Topletz-GlobalSpying-PAPER.pdf I will copy paste the majority of it, some small parts I did not though. Also I would like to point out that one of the authors, Steve Topletz, is a highly controversial figure in anonymity circles. On the other hand, Jonathan Logan and Kyle Williams are not very controversial. All of them have done work on commercial VPN software similar to JonDoNym, they have also contributed somewhat to Tor although Steve is pretty much an outcast in the Tor community, and has a history of being full of shit. That said, a lot of the things he was saying in 2009 in regards to the NSA turned out to be completely accurate, and I actually believe he was one of the first people to publicly point out Roger Dingledines past ties to the NSA. Steve has also given presentations on anonymity at several hacker conferences, as well as at least once at a police and intelligence conference requiring a security clearance to participate in. All of the authors have at least one or two published papers, but they are not very big names in the academic world. They are all pretty well known in the hacker scene though, especially Steve who is a CDC member.