Matt Birchler:

Auto updates only happen when you are connected to Wifi, but iOS won’t stop you from updating on cellular if you tap the update button. The fact that someone could blow through 10% of their monthly data plan (2GB) just by updating Snapchat and Messenger once. This could be tough if you do it once, but Facebook updates Messenger all the time. They’ve updated the app 5 times in the past month, which could work out to upwards of 400-500 MB over just a month.

And:

“App thinning” is not a magic bullet that erases this problem though, as Facebook Messenger, which shows as being 154 MB, still downloaded 99MB of data for its update.

And:

So are giant app sizes a problem? Yes. Do delta updates allow these updates to use less data? Yes. Do delta updates make these large apps a non-issue? Hell no!

And from this Washington Post article, titled It’s not just you: Your iPhone storage isn’t going as far as it used to:

Apple has announced some features that may be able to help with this problem down the line. In iOS 11, due out in the fall, there is a feature that lets you “offload” apps you use less often — deleting the apps themselves from your phone, but retaining enough data so that you don’t have to set them up again.

Screens are getting larger, pixels denser, which means the resources used to support those bigger/denser screens are growing larger. Add to that the steadily increasing complexity of Apple’s SDKs, and it is clear that device storage availability continues to be a tricky balancing act.

But this is “same as it ever was”. Ever since the dawn of the modern computing era, memory and drive size was always a constrained resource and memory and drive sizes grew and software techniques were developed to meet demand with every new generation.