Earlier quoted context omitted.
This is wrong. The "recommended" section of the start menu is written with React Native but compiled to native XAML and not running web technologies. See also: https://news.ycombinator.com/item?id=44125217
Wait.....why develop that small part so differently than the rest?
Every place I've worked which did not use react had steady pushback from UI/UX to move to react. It took active resistance to not use react, even though it didn't make any sense to use.