I think wasm needs some years of evolvement. Many of the good languages like C#, Java, Go or (God forbid) PHP will need a functional cross language and per language framework incorperated shared/cooperating GC which will allow a cross language interchange of objects. Otherwise all wasm will be only app solutions and not an ecosystem like JavaScript.
I am not a super expert and maybe someone can enlighten me but I think that is the biggest hurdle.
It will be just another target for the Java ecosystem, Go ecosystem, .NET ecosystem, Haskell ecosystem, OCaml ecosystem, C ecosystem, C++ ecosystem, ...
I am not a super expert and maybe someone can enlighten me but I think that is the biggest hurdle.