Dioxus Native supports both web and native platforms because they serve HTML and CSS for the web and then on native they turn that into canvas rendered code just like Flutter, not a webview, because they built their own HTML and CSS renderer.

For Flutter web, yes as it's canvas based it doesn't have all the same web features but generally for crud apps it doesn't much matter, especially if it's near zero effort taking your Flutter mobile and desktop app and putting it on the web. With the new impeller renderer and Wasm improvements it has gotten quite faster too.