Moreso than anything technical though, there sure seems to be a lot of bad blood between the group of people behind AssemblyScript and the people behind WASI. This feels like a classic case of small initial technical disagreements spiraling out of control and turning into a larger conflict fueled by personalities and organizational politics. I agree that overall this doesn't add confidence to the WebAssembly ecosystem as a whole, but it's not clear to me that the obvious conclusion is "WASI is controversial" as "WebAssembly seems like it might have a problem with infighting".
Furthermore, there are now competing interest groups within the Wasm camp. Wasm originally launched as a web standard: an extension of the JavaScript environment. However, some now want to use Wasm as the basis for replacing containers: an extension of a POSIX environment.
From my understanding WASI never was expected to run a browser. I'd rather listen complains about WIT being very rust-biased.
Also seems to be okay with having a shim in wasm module to adapt to browser behavior, but not the other way around?