I’m disappointed that this headline will lead to more clicks. This is your reminder that in git the branch name is just a pointer to a commit. Renaming that pointer is relatively seamless on GitHub (https://github.com/github/renaming?tab=readme-ov-file#rename...). Also, git 3.0 isn’t forcing this change on existing repos, just new ones that no automation depends on. And if you really like the old name that’s always an option for your repos. Remember, it’s just a pointer.
The other git 3.0 changes are more consequential and worthy of discussion - changing from SHA-1 to SHA-256 for greater security and performance, changing the storage format for performance and introducing Rust.