Before I go into detail about why I'm not in support of Atheism+, I'd like to preface the post with a statement in advance of a potential flood of Atheism+ supporters: My objections to Atheism+ does not mean that I am opposed to the platforms of social justice, gender equality, women's rights, LGBTQ rights and racial equality espoused in Atheism+. I very much support these things, but I recognize that these are not borne of atheism at all but rather basic human empathy and compassion. So do not assume that I am somehow a "misogynist", "evil", "privileged" or an "asshole" merely for being critical. Now, on to business.
The first reason why I am opposed to the Atheism+ movement is the intentional conflation of atheism with issues that do not have a logical progression from it(As I hinted at above). Nor does it follow that these issues necessarily flow into atheism(perhaps misotheism, though), since there are theistic groups that support many issues in the Atheism+ platform. This does not mean that atheists should not support these things at all. On the contrary, these issues should be encouraged and we have done this with great success. But it is not a good idea to take one thing and attach so many non-relevant issues to it that it essentially becomes an ideological platform, which can so easily turn into dogmas. And having dogmas in a group can be a telltale sign of religious or cultish behavior.
Secondly, this conflation of atheism with so many issues politicizes and obscures atheism to the point of, well, obscurity. The atheism movement is still facing the issues of: society's still-dim views of atheists/agnostics/freethinkers, theocratic encroachments and woo-peddling. To put these issues on the backburner and say "We shouldn't be doing A as much because A is taking too long, so we should be doing X,Y, and Z because I think they're more important" is inviting disaster because although we've made progress, it is progress that can easily be erased by creationists, theocrats and fundamentalists if we don't keep challenging them. In shorter words, the Atheism+ platform tends to treat atheism and it's direct issues as peripheral rather than integral.
Thirdly, because I don't accept the gender feminism and radical feminism practiced by the vast majority of the Atheism+ movement. They claim egalitarianism or equity feminism, but their own visceral responses to legitimate men's rights issues and men's rights activists put the lie to that. You can also see misandry and androphobia in Atheism+ when they've adopted socially destructive theories such as "Schrodinger's Rapist"(forum link) and Patriarchy. It's even been suggested that Atheism+ is more accurately described as "feminism+" or "A+theism".
There is also the problem of the "special snowflake" and "victim complex" cultures developing within the Atheism+ movement(See "Schrodinger's Rapist" again and this link as examples). These cultures are destructive to the stated goals of Atheism+ and generates conflicts where there shouldn't be. As a result, the group has become quite isolated and insular.
And finally, I cannot in good conscience join a group that is so willing and eager to do unethical things such as plagiarism, copyright infringement, smearing and attacking others for dissenting thoughts, and unthinkingly committing credulity all in the name of "social justice" or "the greater good". In fact, it is this continuing unethical behavior, above all else, that is why I cannot support Atheism+.