This is a valid complaint. You simply don't design UI that allows to delete a large number of files with a press of a single button. That he didn't have backups

This is a valid complaint. You simply don't design UI that allows to delete a large number of files with a press of a single button. That he didn't have backups is irrelevant. Even accidentally deleting fresh changes is quite damaging. VS Code doesn't say anything about Git, or what Git is. You can't expect anyone who downloads MS software to be a Git expert.