Ha! I’m partially looking at this issue in my bachelor’s thesis.

It’s not at all necessary to embed a browser, but it’s really easy to transfer your web app to a “near native” experience with stuff like electron, ionic, cordova, react native or whatever other web stuff is out there. The issue is mostly that native APIs are complicated and relying on web views or just providing your own “browser” is a relatively easy approach.

Stuff like Flutter, Xamarin or .NET MAUI compile depending on the platform to native or are interpreted by a runtime. There’s a study I use that compares Flutter to React Native, native Java and Ionic on Android and finds that unsurprisingly the native implementation is best, but is closely followed by Flutter (with a few hiccups), with the remainder being significantly slower.

The thing is. I don’t think these compiled frameworks lag behind in any way. But when you have a dev team, that’s competent in web development, you won’t make them learn C#, Xaml, Dart or C++, just to get native API access - you’ll just let a framework handle that for you because it’s cheaper and easier.

Edit: To add some further reading. This paper and this one explore the different approaches out there and suggest which one might be “the best”. I don’t feel like they’re good papers, but there’s almost no other write up of cross-platform dev approaches out there.

Edit2: I also believe that the approach “we are web devs that want access to native APIs” may be turned around in the future, since Flutter and now also .NET offer ways to deploy cross-platforn apps as web apps. I’ll get back to writing the thesis now and stop editing.