For both technical and UX reasons it's in Apple's interest to make app updates lightweight, and those likely far outweigh any driving force they might have to encourage people to move to higher storage sizes.
(1) if it takes a long time for people to update their apps, that's a crap experience that people are having on Apple devices, which goes directly against the grain of Apple's whole value proposition ("use our stuff and your life will be great!")
(2) For technical reasons, it's in Apple's interest to reduce app image sizes; less strain on infrastructure, easier to scale, etc. (300MB * 1.2M (# of app store reviews) = 360 terabytes transiting their networks whenever Uber pushes an update. All that has to be load balanced, CDN'd, etc.)
(1) if it takes a long time for people to update their apps, that's a crap experience that people are having on Apple devices, which goes directly against the grain of Apple's whole value proposition ("use our stuff and your life will be great!")
(2) For technical reasons, it's in Apple's interest to reduce app image sizes; less strain on infrastructure, easier to scale, etc. (300MB * 1.2M (# of app store reviews) = 360 terabytes transiting their networks whenever Uber pushes an update. All that has to be load balanced, CDN'd, etc.)