[wavemode]

How would a server not written in Java support Java mods?

[rumblefrog]

It'd have to be a hybrid, with more of the expensive parts rewritten in a more well suited language.

[owlstuffing]

Right, that’s my take as well. But on the whole I don’t see Java itself as being fundamentally less performant, particularly with JDK 21+. Architecture choices in either language make or break performance.