So the "master" branch is not kosher anymore

The origins of the debate go so far back that they are lost in the mists of time, but a good starting point (which contains references to prior debate) is an Internet Draft from 2018 titled Terminology, Power, and Inclusive Language in Internet-Drafts and RFCs. Some especially woke communities like the Python community had already started applying some of the recommendations in this draft as early as 2019, but things really picked up steam in 2020, with the murder of George Floyd.

On messages and message-passing

Over the decades, numerous software system architectures have emerged which require invocations across subsystems to be done via message-passing instead of programmatic interface method calls. Such architectures are so common that many programmers have come to regard message-passing as an end in and of itself, oblivious of the fact that it is nothing but a (poor) technical mechanism for accomplishing a certain architectural goal.