Feels like this is basically Flash 2.0. I'm skeptical anyone will use Flutter primarily for a web app, seems more like an after thought approach if you already have an desktop / mobile app.
I have to agree, I wouldn't use Flutter only for web. There are better web-only frameworks out there (not to mention the vanilla approach based on HTML+CSS+JavaScript).
In my opinion, it's a nice "add-on" feature for teams who already have an app running on iOS and Android. For simple apps, these teams are one command away from running things in the browser, for more complicated apps, it's a bit more complicated, but I believe with clean code it shouldn't be too difficult to tweak the app so that it runs on the web.
Also, I believe that the web and desktop is not yet labelled "stable", but they are available on the stable branch (if I understand things correctly, though I could be wrong, it's slightly confusing).
The accessibility is not great yet, in fact, I believe that's one of the main reason why it's not yet stable. The "tabbing" could probably be fixed, though, so maybe it's just the demo app that didn't take care of that. Here is a resource on how an agency made a Flutter project to test Flutter's abilities on desktop (which has similar challenges to web) https://blog.gskinner.com/archives/2020/09/flokk-how-we-buil...
THE BRIEF: Showcase Flutter's capabilities to create apps that feel at home on every platform and device: iOS, Android, Mac, Linux, Windows, and the Web.
OUTCOME: For Google’s Flutter Engage event we launched Flutter Folio, a scrapbooking app that purposefully considers the capabilities, user expectations, input devices and idioms for each platform. Impressively, over 95% of the code base was shared between platforms.
Two years ago, I built an interactive Flutter app to administer surveys. It supported branching based on user input and displayed a summary of responses at the end. At that time the only major challenges were poor documentation and a tiny community.
Feels like this is basically Flash 2.0. I'm skeptical anyone will use Flutter primarily for a web app, seems more like an after thought approach if you already have an desktop / mobile app.