As atheism is spreading through Europe, so is islam. Atheism is NOT going to defeat islam, regardless of whether a country the size of China squashed some little uprising of islam. As atheism creates a spiritual vacuum, something will rush in to fill it.
With China, part of it is just inertia for now. It’s not because of the persuasive power of athiesm.
Besides, the Crusades did just a fine job of keeping us all from speaking Arabic by now.
Are you aware that a large part of the Middle East, now Muslim, was once Christian? So too, Asia Minor.