Redirecting stdout to avoid banners while `import`ing

The same trick as in __is_root_module is precisely what is used in Nemo to not print the banner when it’s loaded from a hardcoded list of packages, I don’t think it’s possible to extend this list. As mentioned in the issue you linked to, you could set the environment variable ENV["NEMO_PRINT_BANNER"] = false (but it’s not documented and might not be supported in the future).