It looks like the team behind it have been moving it towards more of an open standard over the last year. There's now a CLI reference implementation, and the Jetbrains IDE's have an implementation for it.
There's also a thread for Zed about a path to implementing it there [0]. Hopefully it'll become a bit more common over 2025.
[0] - https://github.com/zed-industries/zed/issues/11473