This is certainly a topic that generates a lot of opinions both ways, not just here, but on many other projects.  Based on that, I don't think it's fair to blame Victor for bringing it up for discussion.  This is and has been an industry discussion for many years (master/slave as it relates to technology was named the most politically incorrect term in 2004).  Victor simply brought it up here.

All of the same arguments and counterarguments have been mentioned in these past discussions.  You can argue that this is ridiculous and political correctness has gone too far.  You can argue that this term (master/slave) perfectly reflects the model.  You can argue that it's not the same relationship as parent/child.  These are probably all valid reasons to not change it.  But, I think it's mostly because it's what we're used to.  

Here's an idea -- find a friend and explain to them that there is a concept in computer science where there is a group of 'things' and exactly one of those things is the main point of contact or first in line, but the other things around it that either get direction from that main one, or they are exact copies of that main one, or they are downstream from that main one.  Sometimes it's because if the main one isn't available, then one of the others is ready to take its place.  Or sometimes it's for other purposes (like IDE).  Really set the stage in describing what it is.  Then tell them it's called master/slave.  They probably won't believe that name because it's a little shocking.  We take it for granted, but it doesn't really describe the situation.

I know I'm simplifying and I'm probably not 100% accurate, but I think you get my point.  Except for the fact that it's imbedded in engineering and computer science and we know it, there's not really a  reason for it to be called what it is and there might be other alternatives that are better descriptors.

Personally, one that I've never seen suggested, but one that I think can be used to describe the relationship of "one in charge and others follow, but can take over" would be alpha/omega (as in a wolf pack).  It's a little stronger that leader/follower, doesn't imply the same structure as parent/child, and allows for the idea that an omega could take over the role of an alpha.  Plus, it's very neutral.  Just too bad the guys who originally coined the phrase "master/slave" didn't use "alpha/omega".  

(for the record, political correctness sometimes drives me crazy and I may not see a need to change something like master/slave, but at the same time, I can understand why other people would like to see it changed)

(second aside - I don't recall that there were arguments a few months ago on the PR to make the docs gender neutral.  Maybe people were against that too as being 'too politically correct', but they didn't feel the need to talk about.  To me, this issue is similar to that one.)