IMHO, rust and go are two differents things. The reason I choose Rust is because it is fast and calling C code from rust is supported really well since Rust's goal is to become a system language. Navidrome is just calling the ffmpeg binary. While in my project, I've compiled the neccessary parts of ffmpeg myself (thanks to vcpkg) and call the function directly from Rust. It leads to smaller and fully static final binary (because no ffmpeg bin) as well as faster transcoding time since we don't have to wait for the ffmpeg binary to finish transcoding the whole file before load the result from the filesystem to the memory.
Would it have been impossible to submit your changes to Navidrome as pull requests?
You can see here. This is the biggest reason why I've decided to start my own implementation. Beside, I share my server with several friends so I want a mechanism to prevent mixing musics from different people.
Does this import the Navidrome database?
This could be a feature request in the future. I could add a python script to import users/songs/playlists/playcount/etc from Navidrome.