Yep. These things have been solved by massive investments. The question is, can WASM as a language (not an implementation) do something JavaScript can't?
The answer to that is no. But innovating at the language level was never a goal for WASM; quite the opposite, as simple as possible so it can be compiled and run anywhere.
Wasm can do 64-bit integers, SIMD and statically typed GC classes.