Re: Internal storage space
As Izzy has already surmised, via comment, the new device likely comes with a lot more space taken by the pre-installed apps and system data. That is what I believe is the problem. If you want to save space by stopping the default apps from updating, you can try to disable them in the apps portion of your android configuration menu, or, if that doesn't work, then this guide explains how to force disable apps using adb from a computer, though to get rid of the pre-installed versions' files, you need root.
https://www.xda-developers.com/disable-system-app-bloatware-android/