Yeah, exactly. The initial prototype turned out to be quite slow - a lot of optimizations are needed to be fast. The version as of now is 4x faster than that initial prototype, and 2x faster than the JS version. And we are working to make it even faster.

The good news is that most of those optimizations weren't specific to Java, like work in V8 (that helps any Chromium-based-browser running WasmGC) and work in Binaryen (that helps any Binaryen-using toolchain, like Kotlin and Dart).