Why did Anonymous Remailers disappear?

There are still a bunch of networks operating, and a bunch of tools under development, like https://sec3.net/yamnhelp/ and https://github.com/katzenpost/

Remops is a good place for coordination amongst remailer operators http://lists.mixmin.net/pipermail/remops/

Mixminion network statistics: https://www.mixmin.net/echolot/

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