Concrete Python applications wouldn't be 100x faster if re-coded in some low level language.
In most places where performance matter Python packages would be using either C extension, Cython or numba to get near native performance. Pyodide is able to build those packages (except for numba). So overall it's currently 3 to 5 slower than native Python (which uses C extensions). See detailed benchmarks in https://hacks.mozilla.org/2021/04/pyodide-spin-out-and-0-17-...
In most places where performance matter Python packages would be using either C extension, Cython or numba to get near native performance. Pyodide is able to build those packages (except for numba). So overall it's currently 3 to 5 slower than native Python (which uses C extensions). See detailed benchmarks in https://hacks.mozilla.org/2021/04/pyodide-spin-out-and-0-17-...