Honestly, I think that a lot of the confusion is going to come down to the fact that you're not an American who is getting dragged into socio political issues that are largely centered on America and American society. That is going to be extremely confusing for you, but understand that most of this discussion is by Americans to other Americans.

> Like I've said though I think of 'master/slave' as perfectly fine descriptions regarding their function

I disagree with this. Master/Slave is in fact a pretty terrible description of most of these systems, and appears to have been shoe horned in.

In most master/slave systems the master does all of the work, and the slave nodes exist either for duplicate read capacity, or as a hot standby in case the master fails. This is not the way that historical masters and slaves interacted, to say the least. I believe that "primary/secondary" or "primary/standby" is actually a much better description of the actual function of these systems.

> white vs black, bright vs dark, , "shining bright light" vs "tempted by darkness", etc, it was almost a Eureka moment: "How can people think of skin color there?"

Some of those are tricky, because lightness and darkness is also a good faith description of how human vision works.

But who would see black and white as a description of skin color? Pretty much every American. There is some nuance to terms like whitelist and blacklist (that I have not yet made up my mind on, btw), but when it comes to naked terms like "black" and "white", that is exactly how Americans refer to each other's skin color.

Maybe it's different in your culture. Again, a lot of the people discussing these things are Americans talking to other Americans.

> 'because a black man was murdered by police in a country across the Atlantic, and now they are looking to prune any mention of slavery from everywhere they can find it'

That is a pretty poor explanation of the phenomena at hand. A better description would be "a murder of a black man triggered massive social upheaval and a society wide moment of soul searching about the nation's history both of slavery and poor post-slavery treatment of black Americans. This change has included everything from significant reversals in opinions on policing, the Black Lives Matter movement, the naming of military bases, public display of confederate monuments and flags, all the way down to an investigation of the use of language in software engineering."

The discussion around the use of terms in software isn't because "a black man was murdered", it is because America is experiencing massive social shifts around how we treat race in America. A discussion of how we name pieces of software is probably the absolutely smallest portion of a massive change.