Sometimes you do just want to use off-the-shelf libraries for things and not need to re-implement them yourself. If you already have a web app you’re building around, it’s annoying to need to rewrite bits of it - especially rock solid 3rd party libraries - unnecessarily.
Another consideration is that any webview<->native bridge is going to impose some kind of bridge toll in the form of serialization and message passing (memcopy) overhead. You can call into WASM from JS synchronously, and share memory between JS and WASM without copying. Sync calls from webview to Tauri native code doesn’t appear to be possible according to https://github.com/tauri-apps/wry/issues/454
Finally, security posture of native code running in the main process is quite different from WASM code in the webview. I maintain a WASM build of QuickJS and I would never run untrusted JS in real native QuickJS, whereas I think it’s probably safe enough to run untrusted JS in QuickJS inside a WASM container
