Keep in mind, that some of this behavior is response to Congressmen/women asking Apple to make updates automatic and transparent, so consumers are protected. It went through news few years ago and Apple has promised to do so. And did so. My iPhone and iPad update applications each night automatically. System upgrades I have to allow... Same for my Android.
Result is bit mess as Apple/Google/Microsoft make its best to find choices suitable for most users - and someone in less than common situation gets burned. All companies face same issues - remember Microsoft pushing whole multi-GB Windows 10 upgrade package on Windows 7/8 machines _before_ even asking if people want to install? And then installing on its own if you did not specifically say No and only dismissed dialog? And (may be) deleted the multi-GB installer file if you said No... Your data and your drive space. Basically "stolen" by system manufacturer if you did not want this happen... Lots of people were unhappy at that time.
It is messy problem for manufacturers how to handle this - too many options for most users to make reasonable decisions - or even understand consequences of decisions. Some unique and different users with specific conditions - e.g., most wifi in the US can be considered "unmetered" - but it is not true for some in extreme conditions. Even more so in other world countries.