The etymology of "master" goes back at least to the Latin "magister" meaning "teacher", and is used in a multitude of contexts where one person is recognized as having some kind of revered knowledge or authority about some topic.
While I don't agree with the position that the word "slave" be expunged from tech for some putative role in trivializing historical slavery either, at least the argument does have a plausible premise. The anti "master" crowd though is laughably ignorant of language.
Well, if you start arguing this way, then you can also go all the way back and muse about what the word meant in Proto-Indoeuropean.
It's still obvious that the modern use of the master/slave combo comes from centuries of slavery, not from any prior meanings. As OP said, that can be shown by studying their meanings outside the technical context. The original meaning was retained in Academia but merely as jargon. Magister artium is a "master degree." There is no "slave degree", though. There is also "mastery", master/apprentice, and so on.
In other words, the offensive component of the combo is "slave", not "master." You can safely continue to use the master/apprentice combo.
While I don't agree with the position that the word "slave" be expunged from tech for some putative role in trivializing historical slavery either, at least the argument does have a plausible premise. The anti "master" crowd though is laughably ignorant of language.