Java is the original version from Mojang/Notch. There’s always been enough of a community that killing it off to move away from Java would break so many extensions and servers would see an active revolt.
There is the non-Java version (Bedrock), but that’s not nearly as extensible.
Ah, I had misread "minecraft" as "microsoft". I wasn't aware minecraft java was a thing. Crazy they have their own java implementation!
Switching to vulkan breaks all the extensions too