Wrong.
According to the United States Seventh Court of Appeals, which stands as currently existing US Court Precedent, Atheism IS a Religion for First Amendment purposes.
And really, in terms of the Constitution, that's all that matters -- it does not matter if Human-Sacricifing Satanists claim that their Murder-Cult is a "religion", the Courts of the United States say that it isn't -- just as the Courts of the United States also do not protect the Polygamy-Harems of Old Mormonism as a First Amendment Religion.
But according to the Courts of the United States, in terms of Our Constitution: "Atheism is, among other things, a school of thought that takes a position on religion, the existence and importance of a supreme being, and a code of ethics. As such"... Atheism IS a Religion.
And therefore, Atheistic-Religionism is THE ONLY First-Amendment-Recognized-Religion which enjoys a $500-Billion-dollar-a-year Publik-Skool Government Subsidy in favor of its own Evolutionistic "Creation Myth", over and against the Creation Theories of all other Religions.
As such, Atheistic-Religionism in America is the greatest single beneficiary of the Government Establishment of Religion in the history of Mankind.
Best, OP
Even if atheism was a religion (it isn't), it wouldn't matter. Evolution isn't atheistic. You have no argument.
In this case only those atheists residing in the US can be considered as belonging to a religion.
I don't live in the States but in Canada. I am an atheist, which in Canada is not a religion.