Well you can't even compile Ruby, Python, Node, or Perl to WASM, since you can't compile dynamic scripting languages to LLVM. You could, for example, interpret Python by compiling the CPython interpreter to WASM (though that would mean an absurd bundle size), but this doesn't solve your problem since the python garbage collector is in the CPython source and you can't just remove it nor can you use a different langauges garbage collection because every language represents objects differently.