Oh you might be right. But there is a reason its not used. One of the reasons is the bootstrapping problem.
The growing use of Radicle in the Nix Community opens up an opportunity to find a holistic solution for content addressing.
You implied I didn’t know about the fetchipfs function but I knew about it after Nix and IPFS · Issue #859 · NixOS/nix · GitHub and believed it to be not ideal for multiple reasons even though I forgot about the details in the meantime.
But @warbo already works on promising creative ipfs fetchers: nix-helpers/helpers/fetchGitIPFS/fetchGitIPFS.nix at 6134e5d541274251ec10a1ec69165a73a773a6b0 · Warbo/nix-helpers · GitHub
After that I thought conversion between hash and identifier types would be the first step see https://github.com/NixOS/nixpkgs/pull/423507