IMHO WASM is the perfect replacement for native plugin DLLs for DCC tools like Maya or Photoshop (but not a replacement for a scripting interface which such applications usually offer too in addition to DLL plugins).
Instead of having to distribute a multitude of DLLs for each OS/CPU combination, you only distribute a single WASM module, and the WASM runtime that's integrated into the DCC tool takes care of the platform-specific details. And WASM is also easier to sandbox than DLLs, so a crash in the WASM plugin can't take down the entire application.