According to the README/FAQ:
This error is thrown if a package requires a dependency without adding it in its dependencies or peerDependencies list. In the absence of such a definition, we cannot reliably report the size of the package - since we cannot resolve any information about the package.
In such a case, it's best to report an issue with the package author asking the missing package to be added to its package.json
However, @rc-component/picker is indeed a dependency of [email protected].