As of Emacs 31.xxx byte_compile.sh runs onto the rocks with any package that generates .el files and that doesn't add a lexical binding cookie to the generated file. prescient-save.el being an example. Often the fix is very simple a call to (elisp-enable-lexical-binding), but either needs to be done in the particular package called by radian-use-package or perhaps could be done at the radian level via an advice or something.
One would expect eventually all emacs packages will be fixed, but a workaround of the radian level would be great in the meantime.