well, its unfortunate that React Native didn't work for them. i think RN is great solution and direction for mobile in general. sure it can be improved but at the moment, it is the best we have for cross-platform mobile development.
Not sure what the issue is except that it is yet another language to learn.
Google designed it to be easy to learn for other devs. I am mainly only experienced in Java and some Kotlin, and I found Dart easy to pick up.