Those feel like they were created by orders from top management, because of some strategic decision (microsoft needed a flash alternative, or a Windows 10 store UI framework etc).

They don't feel like the product that would come if DevDiv did their best to produce a sane UI framework. They feel rushed, semi-overlapping, half-finished.

I imagine it should be possible to make just one more xaml framework which is cross platform, and much better than WPF (and it's derivatives), and much better than the js alternative (Because of deployment, not least).

I'm not sure if there is any incentive for ms to put their weight behind it however.