The branch name "master" does not have "golden master" or "master copy" roots: https://mail.gnome.org/archives/desktop-devel-list/2019-May/...
I think treating this human relationship as a light hearted metaphor disregards the gravity of this painful history. Plenty of alternatives exist, and if one doesn’t in someone’s eyes the brilliant thing is new words and meanings can be invented.
I accept criticism of using master/slave as a consequence of the actions taken by citizens in my country in the past. I’m willing to accept responsibility even when my self and family aren’t at fault.
Edit: A second source of word history to review https://econoben.github.io/2020/10/20/master-slave-terminolo...