Why though? Flutter was built for Dart and, while not my favourite language, it does that job very well. When the major drawback of all multi-platform frameworks tends to be performance, how does using a much slower, non-compiled language improve things?
Because companies were already paying for it. Where I work now moved to Teams and they openly said it's not as good as Zoom, but we need to move because we're already paying for Office and so it doesn't make financial sense to pay for an additional duplicate service.