A number of your objections are responding to strawmen. For example, you say it’s just plain wrong to say that atheists claim there’s no need for any worldview. Just read the whole sentence. I was setting up a dichotomy of exclusive alternatives. The point is that if the atheist rejects theism for being irrational, the atheist faces two choices: either she has a better worldview in store or she denies there’s any need for a worldview. Do you see a third option for the atheist?
You say it’s a bait and switch to go from talking about atheism to talking about secular humanism. But “atheist” was originally a pejorative label applied by religious people such as Romans or Christians, like “barbarian” or “pagan,” meaning “foolish, trouble-making foreigner.” The issue wasn’t so much whether any god at all exists, but whether the state-sanctioned gods are powerful enough to compel the subjects to obey the human leaders. Thus, the Romans called Christians “atheists.” Later, secular philosophers analyzed the concept and found the question worthy of debate: Does any god exist?
The real fallacy, though, is to pretend that that question can be entertained in the abstract as though the “atheist” didn’t tend to have a positive alternative worldview. The Western philosophical debate isn’t between atheists and Christians, for example, but between naturalists, materialists, secular humanists, positivists, neoliberal consumers, or transhumanists, on the one hand, and Christians on the other. There’s no such thing as a mere atheist, so the fallacy is pretending there is. The question isn’t just whether God exists, but whether any ultimate explanation can or should be perfectly rational or whether some myths are needed. I talk about this more in “Why Theism and Atheism are both Laughable” (link below).
You say it’s religion that claims to rule the world. I’m afraid the Anthropocene kicked into high gear only with the rise of modern secularism after the scientific and industrial revolutions. Now it’s consumers and neoliberals that are actively ruling the world in the name of humanistic progress, not for the sake of Jesus or Allah. (See the second link on the problem with environmentalism.)
You say we don’t need myths to live in peace, but that’s just an assertion. It’s a question of not strawmanning myths and religions with positivistic presumptions. Myths are stories. Have you ever read a fictional story? Perhaps watched a movie? Did you stop and leave halfway through, saying, “This story is absurd. None of it is factual. What a waste of time!”? No, because you suspended your disbelief for the sake of entertainment.
Likewise, if we’re humble enough to realize our worldviews rest on nonrational assumptions, we can entertain ultimate explanations with aesthetic and social standards in mind. So we wouldn’t think of gods as mere objective facts, since that would presuppose the philosophies of positivism or naturalism, which rest on their own irrational foundations. We’d think of gods as treasured characters and we’d have faith in them to make life meaningful.
You may be relieved to know, though, that I’m an atheist. The gods of the major exoteric religions aren’t worthy of being worshipped. The belief that they exist is exceptionally irrational. But Nietzsche’s point about the need for aesthetic standards to prop up a worthy transhuman religion or way of life shouldn’t be dismissed.
You say the need for myths wouldn’t prove that gods exist. But the above article is about atheism, not theism. I’ve written dozens and dozens of articles against theism, on Medium and on my blog (see the third link). The above article is about the entirety of atheism, meaning the negative claim and the predominant positive, alternative, secular worldview.
The question of secular morality is a big topic. If the basis of that morality is only an agreement, as you say, as in a stipulation like the social contract, does that make secular morality a game like chess? Once you agree to the rules of a game, it’s unsportsmanlike to break them. So are evil people merely unsportsmanlike? On the contrary, evil disgusts us because we have irrational faith in the secular myths that prop up our moral standards. Note that those standards aren’t propped up by objective facts, because of the naturalistic and genetic fallacies.
You say atheists don’t dismiss religion along with theism. I beg to differ. Lots do.
You say atheists claim only that theistic beliefs haven’t been proven. Yes, that’s the explicit meaning of atheism, but the implication is that atheists have a superior way of life. However, if we discover that that way of life amounts to an alternative religion complete with faith-based idols that replace the old gods, we have something in the way of incoherence and hypocrisy on our hands, don’t we? And if you don’t think secularists have faith-based idols, you haven’t looked hard enough.
Stomping your feet in response to transhumanism doesn’t amount to much. The argument is what it is. Transhumanism is an example of a secular religion complete with a faith-based substitute for God, the faith being that technology will turn us into gods.
Again, you say this has nothing to do with atheism. And I say atheism doesn’t exist in a vacuum. There’s no such thing as a mere atheist, just as there was never any mere barbarian or pagan or savage. Those pejorative labels were dismissals of positive, alternative worldviews and ways of life. Transhumanism is part of a predominant atheistic, secular worldview and it threatens to make that worldview incoherent.