All these languages du jour should go out of their way to answer the question: "why bother?". 10x faster than react. OK cool. Except unless it has something like react native it's irrelevant if you might want to write an app in future with any sort of code reuse since you'll be tied to the web (unless you want the inevitable world-of-pain of trying to integrate this preprocessor into your xcode/android builds...).
I hate it when people say, (and I'm paraphrasing) "well there's software for everyone's needs" but there really is. Everyone participates in different communities and ecosystems, and not everyone is riding the latest FluxTypeGoNativeAngular2 rollercoaster.
There are plenty of people who don't even use React because why bother?