I'm not sure if the web render engine has gotten better since then, and am too lazy to look up the links rn, but threads should be easy to find using HN search.
Still seems like a common source language + GUI toolkit that targets the web platform and various native platforms (mainly Android, iOS, macOS, Windows, and desktop Linux of course) without significant overhead has not been achieved yet. And it's questionable whether it's possible, given the special requirements (and capabilities) of the web platform and the different native platform.
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.