I'd be grateful if someone could say a bit about why GNUnet is interesting. I looked at it some 4-5 years ago for some P2P work, and concluded at the time that it was entirely unsable. Has much changed?

I've been revisiting this page hoping someone will answer your question, and I worry that it's significant that nobody has.

Me too. When I think Web 3 as being distributed this is the kind of thing I imagine. Not crypto. :(

To handwave tremendously, it's another private internet implementation a la Tor or Freenet. They have a useful Applications [0] page.

[0]: https://www.gnunet.org/en/applications.html

From the FAQ [0]:

> For users, GNUnet offers anonymous and non-anonymous file-sharing, a fully decentralized and censorship-resistant replacement for DNS and a mechanism for IPv4-IPv6 protocol translation and tunneling (NAT-PT with DNS-ALG).

[0]: https://www.gnunet.org/en/faq.html

README.1ST of 0.16 tarball:

> WARNING!

> =======

>

> The following is a list of issues with GNUnet 0.11.0 that will need

:|

> 0.11.0

:(

probably a remnant... but who knows?

> This is a new major release. It breaks protocol compatibility with the 0.15.x versions.

No, it's a minor release. It breaks compatibility, so it should be v1.0.0

Even strict adherence to semver allows this because the major version is 0. You can do anything you want until your 1.0 release. https://semver.org/ says:

> Major version zero (0.y.z) is for initial development. Anything MAY change at any time. The public API SHOULD NOT be considered stable.

That said, the GNUnet project has never, AFAIK, said they are following semver. Semver isn't the only versioning scheme around.