It's under Apache license. I think the ethics of code placed under that license include "you may use this; you may rely on being able to continue to use this; if you don't like the direction the main package is taking for whatever reason, you may fork it and [optionally] release your fork under Apache as well."

Is it unethical, though? The entire point of OSS is that you cannot revoke the license once granted. A hostile fork is the expected result of Chef's actions.

The zeroth freedom is the freedom to use the software for any purpose whatsoever. That inherently must include purposes which the author finds unethical, even abhorrent.

It’s legal, no doubt about it.

But forking with the intention of helping people run concentration camps and changing the authorship of the commits? Doesn’t fit into my model of ethics.

If forking a public github repo is unethical we are all screwed.