An atheist can care about such matters. I care enough to engage in conversations. It all comes down to whether or not I am ultimately convinced of a particular theism ... and in my case, I have not yet been convinced of any, but I always learn something from each such discussion. In fact, Christians have been singularly helpful in helping me refine my Marxism radar, as an example. Discussions on Biblical teachings usually give me new and interesting contemporary applications for parables and stories, as another example.
Theistic discussions always have a draw because, by their very nature, they reside at the far end of the "importance" spectrum which always hold humanity's curiosity, so it really isn't accurate to say that atheists don't care about such things; they simply have not yet been convinced ... but that does not say anything about what tomorrow will bring.
It's the Marxists and other secular religionists' ... who disingenuously claim to be "atheists" ... who simply refuse to be convinced of any competing theology. Atheists have no existing theism to be threatened, and thus have no motivation to refuse to consider new information. Warmizombies, however, need to lash out in irrational defiance to protect their Climate Change theism.
Also, another key point is that atheists do not hold the belief that there are no deities. As such, you won't find any actual atheists claiming that you should believe that there are no deities. Atheists don't have any theism to impose onto anyone else. If someone is telling you that you should believe that the earth's average equilibrium temperature is somehow increasing, he's not an atheist.
It really is this simple. How do rational adults get this wrong?