Atom is built on a desktop version of Chrome, so it’s not compatible with different architectures. Any attempt to make it compatible would require a significant effort from skilled developers and is not in the scope of what the dev team has the time, expertise, or energy to do (I’m not on the dev team, but this question has been asked before, so I know what the answer is).
The software is completely open-source, of course, so anyone who wanted to attempt a port would not need to write that much in the way of new code. All that needs to be invented is the base layer (the desktop version of which exists in a stand-alone form as the Electron framework). Once that’s built, the Node-enabled web app code that makes up most of Atom’s interface should just work.