XAML is a template, JSX is a DSL. A template kills scope, duplicates coding semantics, messes up app flow with bindings and needs dependency injection to get local scope back - all of this has been solved with JSX, which now pretty much fulfills Silverlights dream: https://news.ycombinator.com/item?id=16198843

The crazy part is, that you can share code and eco-system components among these targets, no matter if they're native or otherwise. Here's a shell applications for instance that uses react-motion to shift stuff around: https://github.com/gaearon/react-blessed-hot-motion

Microsoft seems heavily invested in it as well (react-windows, reactXP, UI-fabric, ...).