There are 7 billion people and at minimum, tens of millions of them are massive assholes and idiots.
I mean, there is though?
"Just get over it", "need thicker skin", "the cost of doing business in open source", etc.
You did it in your own comment even. Making excuses for shitty behavior, as if it's some natural law like gravity.
What do those sentences mean, if not suggesting that the maintainer is the one who made the wrong decision (by taking offense to the email)?
They mean that I don't see really any value in your framework of 'fault' vs not. We are still left with the question of 'what do you do'.
For a project of this magnitude, I don't think the maintainer made the wrong decision. But just because someone else is at fault does not mean that every decision by the other party in response is a good one.
My point was: I don't think this post will serve as a reminder to be nice to OSS maintainers (as the original comment I replied to was saying), because the majority of comments I see are some variation of "toughen up" directed at the maintainers.
The maintainer can decide what to do about it. Whether or not that is the wrong decision is a different issue. (Anyways, there are many other reasons why it might not be maintained, than only due to receiving such a email message; e.g. because you are injured or because you have other work to do (which is what is mentioned in the README.md file anyways), or whatever other reason that maybe other people don't necessarily know.)
Nevertheless, some people who will maintain the project (not necessarily this one, and not necessarily) should do so even if people send such bad messages. That does not mean that everyone will; what they decide to do about messages they receive is their own choice. This is why FOSS is important; you can fork the project and make your own modifications, if you disagree with the maintainer.
Statistically speaking, the likelihood that there's an asshole somewhere that you'll run into in the course of your lifetime is near 100%, so it is some natural law like gravity. Do you have a proposal for a solution to this problem, or are you just calling people victim blamers for acknowledging that these people exist?
If someones only contribution to the conversation is blaming the victim of harassment for not have thick enough skin, they shouldn't be surprised to be called a victim blamer.