I always think of "master branch" in the same way as "master copy", and never associated it with "slave branches" or whatever. Renaming all the branches seems like needless busywork and frankly, people who would be offended by any use of the term "master", including ones like this, will need to understand the context and motivation of the use of a term as part of growing up and participating in a society with lots of other people. If everyone's right to not be offended were taken to a logical extreme, you end up with this minefield where literally no one is free to speak their mind and has to defend against every possible offended take. You can't even use a word that has a specific meaning if it also has some other meaning. It's just blasting holes in language and thinking and conversations.