Nope. And I, if I was Facebook, would not be proud of this stats. Don't put all your eggs in the same basket. Now, FB and Google has the opposite profit behavior. And I think it will be bad to both of them. Maybe they will meet in the middle, and lose their cash cow.
This is a strange complaint. A couple years ago, Facebook was making 90% of its money on the desktop, and people were saying the same thing. Now they have (very successfully) diversified, and the complaint is still there?
If it was a problem, why would it not be now? Only because it is said that the mobile basket is bigger? It may be less deep. Google still makes a lot more than FB.
Desktop revenue is growing too. Just not at the same rate as mobile. They have not ignored their desktop platform, in fact, the ad product is still designed for creating desktop ads, while they offer lots of tips and tools for optimizing them for mobile.