Is ProGuard or similar widely used these days? Is it good enough?
There was a parallel trend of some really awesome apps clocking less than 4MB, which I attribute to good tooling. I wonder if Gmail, Facebook, et al have stripping & such turned off, or if they just have huge asset stores?
A motorola droid was super fast, I had it for years.
If you made a brand new motorola droid today with the same exact hardware and software it would be too.
Here's a chart showing apk bloat for popular apps over time: https://sensortower.com/blog/ios-app-size-growth
It's for iOS but the same logic follows for android