To be fair, making an app in 2008 (when WPF released) with JS was a completely mess. WPF was usable and they introduced data binding/MVVM. In 2018 (React/Redux), it's fair that JS seems to be advanced vs WPF. Though its productivity isn't so bad (unless you want to fully customize everything).
Also on "to be fair", JS libs have a nasty habit of either completely redoing the API, or dropping maintenance entirely and encouraging everyone to switch to the new hotness which also has a completely different API, every 6 months or so. It's a lot easier to have a nice API if you get to rewrite it on a whim and tell anyone who doesn't like it to fork off. WPF may be weird and messy, but your app will still work unchanged even now (well I think, haven't used it in a while).
