This is a bit longer than I intended, but is my point of view, and not intended to dismiss what you’re saying at all.
I think it’s easy to dismiss conversations like master/slave whitelist/blacklist as overly PC or childish. I certainly don’t appreciate the overly-preachy feeling I sometimes get from people pushing their point of view. And my nature is to find pleasure in giving The Man the proverbial finger. The self righteousness can be intentional on their part, of course, but many times it’s not. I honestly get the similar feelings about the diet-of-the-year fad, too. I have been very lucky in life so far, in that I haven’t struggled with weight or the negative impacts of racism. But I’m discovering that language is an incredibly powerful tool for changing deeply-rooted habits, like which foods you find comfort in, or your default reaction to conflict. When I’ve become an unwilling participant in these changes, I have to ask myself: what is the balance of pros/cons for me and for others? Also, what is my net influence on others who are attempting to do good (no matter my opinion on its effectiveness)? I don’t think I’ve ever changed the default branch for any GitHub repo I’ve worked with. It should theoretically cause no issues at all, I suppose, but I can’t state that with certainty. So there’s a bit of a challenge that I’ll actually enjoy. And I’m not aware of any culture or richness of vocabulary that depends on the dynamic of this set of nomenclature. Besides, I still see words like “serf” and “lord” on a semi-regular basis despite it’s remove from our lifestyles, so these words aren’t disappearing any time soon.
On the other hand, it’s hard to deny that racism has scarred our society very deeply. I remember being shocked when my wife told me how young age was when someone first attempted to take advantage of her for sex. I recently felt the same level of shock when my friend told me that she gets called the n word multiple times every day. If our vocabulary can change our mindset, then maybe removing the master/slave dynamic can be a net positive, like removing the vocabulary of war from our daily interactions. We end up turning to other defaults instead of the old ones. Maybe we end up no better off, and decide to change again. Who knows? But personally I don’t see a lot of downside in the attempt to better our world.