I've never touched Java; do I have a dull and limited computing experience?
I maintain my own Lisp implementation that has a decent object system, exceptions, delimited continuations, compiler and virtual machine, and a whole-document pattern matching language for easy text transformation.
I've worked on early versions of the POSIX threading library for Glibc, Linux device drivers, all sorts of middleware stacks in wireless, VoIP and such.
I started working with 8 bit microcomputers in the early 1980's, writing games and utilities, and dial-up BBS's, using assembly language and BASIC. I had dabbled in 3D graphics and the "demo" scene. I used to code in Pascal and Modula-2 before C. I've worked as a C++ dev for many years.
Java simply isn't something that would interest me. Java programs look verbose and blubby. To be fair, a lot of what I use and have used is blubby, like the C language, Unix shell and whatnot. But I don't need more blubby. I have my fill of blub calories already. The Java platform bloated, and the ecosystem is self-absorbed. To its credit, it has a reputation for supposedly having good garbage collection and concurrency in its VM, that's about it.
I think it's admirable that you have such a wide experience with programming and open source. And I'm sure we could riff on Oracle and the Java platform all day.
But considering airsonic runs on Java, and you aren't developing for it, the only relevant issues with respect to the source language are performance and program size in terms of both memory and storage.
Considering you're storing videos on this server, storing a tiny Java app is a non-issue. And the memory the program itself takes up is meager compared to the memory usage from streaming and encoding/decoding media. If I had to guess, based on the lean interface, it has a lower memory profile than Plex. Performance, again on par with Plex.
So, if you don't have an ideological opposition to Java due to its proprietary nature, then I don't understand why you give a shit if the best media server for your needs runs on it.
I'm only responding to the idea that someone's experience is limited and dull if they don't work with Java.
We can hardly avoid using Java stuff in daily lives. If you use Android at all, you're using Java programs. Lots of web applications have Java back ends.
The premise wasn't that OP doesn't work with Java. OP's premise was that they won't even use applications that use Java. Which is basically everything.
1) insufficient knowledge of the source code behind the tools you use, or
2) a really dull and limited computing experience