For your second one, it looks like it is already implemented in Chromium and Firefox but not Safari. Sadly, it's not new for Apple to be dragging their feet on moving web standards forward.
It took what seems like a decade to get proper WebRTC support in Safari.
> WebAssembly (abbreviated Wasm) is a binary instruction format for a stack-based virtual machine. Wasm is designed as a portable compilation target for programming languages, enabling deployment on the web for client and server applications.
I think wasm is still great without these fixes, but I have lost confidence in the idea that wasm will reach its full potential any time soon.