master has never been a slur, it was never meant to mean insult, it is an honorific title.

A "glass masters of Murano" makes beautiful art with glass, because he's a master in that craft.

Doesn't matter if the word has been distorted to mean something bad for a brief period of human history.

Slave is the offending word, not master.

We should have master branch or master database, but secondary branch and secondary database, instead of "slave" ones.