But as someone who's not a network specialist, I fail to see how this is not a glorified P2P DNS.

Maybe this example helps:

https://github.com/n0-computer/iroh#rust-library

    const ALPN: &[u8] = b"iroh-example/echo/0";

    let endpoint = Endpoint::bind().await?;

    // Open a connection to the accepting endpoint
    let conn = endpoint.connect(addr, ALPN).await?;

    // Open a bidirectional QUIC stream
    let (mut send, mut recv) = conn.open_bi().await?;

    // Send some data to be echoed
    send.write_all(b"Hello, world!").await?;
    send.finish()?;

    // Receive the echo
    let response = recv.read_to_end(1000).await?;
    assert_eq!(&response, b"Hello, world!");

    // As the side receiving the last application data - say goodbye
    conn.close(0u32.into(), b"bye!");

    // Close the endpoint and all its connections
    endpoint.close().await;

IP addresses break, dial keys instead

Modular networking stack for direct, peer-to-peer connections between devices

iroh establishes direct connections whenever possible, falling back to relay servers if necessary. Get fast, efficient, reliable connections that are authenticated and encrypted end-to-end using QUIC.

So in theory a go implementation is possible using a go QUIC implementation that supports the multipath extension.

Our focus is the rust implementation, since it is very easy to use from compiled languages such as rust, C and C++ and to embed into languages such as js and python.

But there are some other projects that attempt to provide a native go implementation: https://github.com/tmc/go-iroh

Edit: since iroh is just a library, it is also possible to link iroh into a go program. Linking a go program from other native languages is a bit of a pain, but linking a C or rust library into a go program is relatively straightforward and high performance.

That being said, if IP ever gets replaced, your iroh based app will continue to work pretty much unchanged. Iroh will just get you the best possible connection (IP or whatever) under the hood.

https://datatracker.ietf.org/doc/html/rfc7250

In the beginning of the project we did use self-signed certs, but due to raw public keys that is no longer necessary. And in any case scary build flags aren't an issue since we control our own rust QUIC implementation, noq.

Also you can join our discord and there's #showcase https://iroh.computer/discord