The /MediaArch x64 argument specifies that MCT downloads a 64-bit Windows 10 Enterprise edition – and in this case, v1909. If you need a 32-bit Windows version, change it to /MediaArch x86.
It's a wonderful third-party tool that helps turn your Windows 11 PC into something more Windows 10-like, which is fantastic ... as a recent update to the app has brought it up to speed with ...