Fair point, I don't think it should have been changed in the first place. But it's been changed whether we like it or not. If it was "main" in the first place I think that's still a better name than "master."
When one is willing to discard that connotation, then, if anything, “default” would be a more accurate name, because the fact that it is selected by default in certain situations is really the only technical difference compared to other branches.
It has had the connotation of "mainline", a synonym for "trunk", in version control since before Git existed: https://en.wikipedia.org/wiki/Branching_(version_control)
Presumably this was originally due to the connotation of the railroad mainline: https://en.wikipedia.org/wiki/Main_line_(railway)
The whole branch naming thing is still only half implemented fwiw. Lots are still master, the default for new branches seems to be main. At my company it is “develop” for git.
Other VCS software uses a totally different name, perforce uses main for example.
I don’t really care what it was, it could have been “killwhitey” and I still would have been against changing it because of the effort involved in changing every repo on earth and the invalidation of every tutorial in existence.