throwaway49496
Software development is not just about the users. Many Electron apps are single dev ventures. It's not easy to maintain multiple different platform specific apps even for a large enterprise. The larger the app the more difficult it becomes.
People prefer Electron because it gives them a consistent environment across operating systems, OS versions/update patch numbers, browser versions etc.
If you write your app to work in all possible combinations of the above - like you'd write a web page - you can use OS web view.
But not everybody wants to do that because it's not as straight forward as just writing your app and being able to fully rely on your environment. Perhaps you actually need features that aren't universally available in the OS web view yet, and performance degradation because of polyfills is not acceptable.
Also, OS web view is usually locked down more than Electron. It's basically a browser without the UI around it. Then you need to hack your own native bridge instead of just using whatever Electron made. I guarantee your version is going to be worse, you simply don't have the combined resources of the Electron open source project.