Fine, but at least make it consistent then. GitHub uses "main" and now this uses "primary", next someone will use "base" and I'm not sure at all how this is better in any way.
That's hardly in the hands of any one developer to make consistent, and it was hardly entirely consistent before. As long as it makes sense in the context of a given project...
In the context of a master password, it doesn't make sense to change it. It's analogous (closely, but not perfectly) to "master key", a term which non-nerds may be familiar with from the world of physical keys (and which term, in that context, isn't going anywhere, in part because, as with this one, there's no reason whatsoever for it to) so gave normal folks a better handle on what it means and how to use the software.
There's no reason they should be consistent. Different git hosts, sure, but a master branch and master password have nothing in common but the name (which is now different).
Amid the currently fashionable trend of language culling, I was mildly surprised to find myself agreeing with this particular change: In git, I think "main" is a better choice than "master", because it more accurately and succinctly reflects the intent.
(In general, though, I think the trend is misguided and counterproductive.)