In my opinion react has been downhill since hooks.. if I could recreate react I'd disallow passing functions or components into props or children.
I'd definitely disable use context
I'd provide simple global state..
For any component if you wanted know what data it gets there would be only one source, props.
Lifecycle methods will be simple: before, during, after..
Probably eliminate function syntax and go back to class syntax which is cleaner...
Discourage typescript but allow prototypes for better autocompletion
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