Checkout the React 19 beta:
https://react.dev/blog/2024/04/25/react-19
These changes seem more quality of life vs some of the lower level performance type changes we saw in React 18.
React Compiler is the more exciting prospect here, current claims are that it will cut out the need for a lot of the efficiency fluff code we have today when using hooks, for example useCallback.
https://react.dev/blog/2024/02/15/react-labs-what-we-have-been-working-on-february-2024
Some new libraries have popped up that claim to be able to provide this now, which means you can start getting ready for React Compiler today if you wish.
Update: checkout this video digging to the low level differences with the transpiled code