More like Sony has an old school management where each division is going against each other.
I mean there's a reason why Xperia phones have mediocre picture quality, despite Sony themselves makes the sensor for other phones like iPhones. Apparently the Alpha (Sony's camera) team doesn't want the mobile team to have good photo quality, in fear of cannibalizing Sony's standalone cameras.
We can learn from history, where Sony Walkman got beaten by the iPod & iTunes despite Sony has their own music label and movie studio. Clearly Sony hasn't learned yet.
The whole thing about Sony is just weird the way they operate things. Like you said, they make the sensors for all the best mobile cameras out there. They Can easily have the best smartphone camera