I'm looking forward to reftable to become the default. It solves many problems with branches, like branches with weird characters created with non-standard clients making a fetch impossible; case insensitive branches with "same" names doing the same; or impossible to create branch FOO because FOO/Something exists.

All those problems just go away when branches are no longer files on disk.

I enabled it in setup script of one large repo I maintain; the main issue is the incompatibility with some people's personal tooling based on libgit2 (some git status tooling in oh-my-zsh), but people do find workarounds.