There is an ongoing tug-of-war over the future of server-side WebAssembly.

One side embraces the idea that Wasm was designed in the context of a broader web platform. Their approach to running Wasm outside of the browser is to transplant relevant parts of the web platform onto the server, and run Wasm within this browser-like context.

The other side sees Wasm as a CPU-independent bytecode, for which the browser is just one use case. Their approach is to standardize a syscall-like interface (WASI), akin to the one an operating system provides to native code.

The source of the rift is that Wasm doesn't specify a particular interface with the outside world, by design. While Wasm itself is portable across platforms, it’s only really useful when paired with such an interface.