I read a gitlab blog[0] where they mention that "master" comes from bitkeeper where there was a master repository and slave repositories.
It does make one wonder, if there was more diversity in CS when these things were being made whether "master-slave" analogies would have made it in or whether other analogies like "parent-child", "major-minor", "leader-follower" or similar would have made it in.
[0] https://about.gitlab.com/blog/2021/03/10/new-git-default-bra...