WasmAppHost is included in the WebAssembly.Sdk pack, and doesn't have a platform specific package.
Since, this is being built for x64, the build defaults to using the app host, which means that we get a single binary file that can be run directly. But this also means that the binary included in the WebAssembly.Sdk platform-agnostic package will target the platform where it was built.

Instead, build with UseAppHost=false, and update the wasm host to use the managed assembly instead.