BlackBox is a Minecraft plugin that will allow you to write plugins in many other compiled languages besides Java. It does what you could do with JNI, but it handles all the Minecraft stuff for you automatically, so you don't even have to use Java's tooling ever again. Because JNI can be very unruley to work with, its developed alongside a Rust library, and a C++ library is planned, although it is low priority.
This plugin is made knowing why this hasn't been done before and why you might not want to do it.
It's assumed that you don't care. This is for the people who are sick of Java, never want to work with Gradle or IntelliJ ever again, and just want to use a language that they actually like (assuming they dislike Java).