Because the architecture is the primary source of the performance issues.

React Native is widely used by the many-billion-dollar company that originated it, so major performance opportunities are not likely to be low-hanging fruit at this point.

There is a major re-architecture of React Native underway[1]. See Lorenzo Sciandra's excellent conference talk for an explanation of what the current limitations are in React Native and how they are planning on addressing them in the near future [2].

[1] https://github.com/react-native-community/discussions-and-pr... [2] https://www.youtube.com/watch?v=7gm0owyO8HU

I just speed read though it, So basically Everything is changed? I am not even sure if that is like a re-architecture, it is more like a a rewrite, literally every apart of the stack, all the way to Javascript Engine. All aiming for 2020 release.

At least the whole stack have many large companies'vested interest in it now so it is unlikely RN will fade out anytime soon. Will be interesting to see how all these played out in 2021/2022.

They will probably slowly introduce the changes one feature at a time in a backward-compatible way in a similar manner to how core react architectural changes are introduced (eg fiber, suspense, hooks etc).

Someone I work with on react-native just sped up large text parsing by 40% or so.