Is going mobile often an economic failure?

The last few years more and more game developers are looking at smartphone gaming, as it sometimes has very high profit margins. Games like Angry Birds and Candy Crush doesn't cost much to develop, but has tremendous profits.

Nintendo recently announced they were leaving smartphone gaming. They first tried selling Super Mario Run at $9.99 with no microtransactions, which didn't go so well. Then they tried microtransactions with Dr. Mario and that failed too.

That got me thinking, do you think games like EA's Command & Conquer Rivals, Blizzards Diablo Immortal, and Bethesda's Elder Scrolls Blades were economic failures? I think they might be, because I think mobile games need to "go viral" to be successful, and there's a limit on how many games can go viral.