I have worked on a few mobile games where there was a big developer push for reducing the app size but it was shot down by management to add more new features instead. A lot of features had expected performance targets to hit before they got the go ahead and it was hard for reducing the app size to have a sizeable difference on KPIs until it got to critical levels.

I think there is also a certain amount of developer apathy towards application size.I was recently talking to a colleague who had worked on a new banking app and they saw no problem with developing, what was essentially a web front end, with the Unity game engine. When I asked if he was concerned the effect on the app size including a game engine would have he said it was what they where used to using and that was more important.