It's exactly what it is, except there is also a browser implementation without plugin. Which also means that WASM/WASI is not a total replacement for containers: just like there as JVM image there will be WASI images. The argument of size given in the article isn't very convincing, when images like Alpine exist.

The problem addressed in the post is more about getting around Rust slow build time than phasing out containers. There's a lot of buzzwords (WASM, Rust, Cloud, etc.) but at the end of the day nothing that isn't easy to do with a modern "boring" stack like .NET.