What's funny to me about your comment is that you actually chose a perfect example of the importance of critical thinking in how we discuss terminology.
The message behind the English idiom you chose is clearly one of self empowerment; /you/ are the master of /your own/ destiny implies independence, freedom, and agency.
In the context of git, and distributed systems more broadly, `master` is specifically chosen for its association with a power differential between one special entity giving the orders, and some collection of other entities taking the orders. In some DB systems, for example, the language is as literal as `master/s`. Even without "s" in use with `git`, there's a clear association with `master` being the branch that broadly holds sway above the other branches.
We chose symbols and metaphors to aid in our mental modeling of complex systems. I'm further amused by your own choice of "policing" to describe a push for cultural healing coming from a minority population. I recommend reading up on the history of policing to see why this metaphor is ill-advised.
> Like, we're just going to scratch a whole bunch of words from the dictionary because someone somewhere is offended?
This is a strawman; nobody is calling for this.
> The other day, people at my workplace were saying that expressions like "blind spot" and "falling on deaf ears" needed to be purged.
Based on your use of "policing" and "[scratching] from the dictionary" I'm wondering whether these folks literally said "purged" in their own language. But otherwise, cool, it sounds like they are exhibiting the positive human trait of compassion. If a disabled person tells me they'd prefer I don't use this idiom, I'd happily find another way of saying the same thing. What's the big deal?
> AFAIK, "blind spot" is not actually about blind people, it's a term related to driving and the angles seeing people can't see in without looking.
This isn't really how language works though, is it? When people are forging associations with words or phrases, they're not opening a webster's dictionary, but rather drawing on a complex web of cultural associations. A more extreme version of your argument here is that it's unreasonable to be rattled by the use of a swatstika in western culture, since the /original/ meaning behind that symbol was one of peace. Nobody would buy that. However, in certain east asian cultures, the symbol is still in use for more positive associations.
The specific choice of `master` as a symbol in distributed systems holds meaning due to its evocation of a power differential. Whether this is intentionally "bad" holds no meaning whatsoever. What does it say about us if we can't honestly hold some degree of empathy for someone who, affected by a violent history of subjugation and dominance, might not love the idea of using symbols chosen for their hierarchical power association?