JS and DOM are popular mostly because they exist everywhere, and there's a large ecosystem of support. In practice, given (until recently) difficulty in hiring,

JS and DOM are popular mostly because they exist everywhere, and there's a large ecosystem of support. In practice, given (until recently) difficulty in hiring, places found it easier to have one JS team than to have one native team for every possible platform (Windows, Mac, iOS, Android, maybe even Linux). And it also does not help that each native platform can have wildly divergent frameworks and practices.