I've been modifying gerrit access files locally, instead of doing this in the UI - easier when you have bulk operations.
To access these files, I need to "git pull origin refs/meta/config" - this is how they show up in the project.
Now I'd like them gone, I'd like not to see them in the project anymore - how can I make files belonging to that ref disappear? How to un-fetch that ref?
Using git-pull you have merged the reference refs/meta/config into the current branch (maybe master). Where have you seen that command line? If you want to modify files in the meta/config ref, you should use command lines similar to those recommended here:
git fetch origin refs/meta/config:refs/remotes/origin/meta/config
git checkout meta/config
//edit... and then push:
git push origin meta/config:meta/config
Now the issue is that you did used git-pull. Using git log --merges --first-parent, try to find the revision where you have merged that branch. And then git git revert <commit-id> to undo that merge.