To make an analogy, right now it's possible to write and include C++ modules in your Python scripts, just like it's possible to do with WASM/JS. But people still use Python, because it's a much faster/easier way to get a specific kind of thing done.

So WASM is a great tool, but not a good choice for building something like HN, where perf isn't an issue. Iteration speed, debuggability, and the GC make HTML/CSS/JS a better choice here.