Apple is the only one that effectively knows the Real Name of all their users, because you cannot do anything on an iOS device without signing up for an Apple Account first.
It's virtually impossible to sideload anything on an iOS device without extensive developer know-how; but for Apple itself to do a targetted attack, would be a trivial task.
Android is the privacy heaven by comparison.
It's relatively trivial to get started with F-Droid and Aurora Store, and then you can install whichever apps you need, without providing any identifying information system-wide, without needing anything beyond the Android device itself.
No PCs, no mandatory 0days, no exploits, no specific software/hardware requirements, no warez, no copyright infringement, just pure free software and a few warning dialogues from Google about the dangers of installing the third-party apps, before you can do whatever you wish with the hardware you paid for, on any Android device of any vendor.
The difference is the open source software is auditable - Apple necessarily isn't. Its not the same.
Its not a user interface problem either, that's just a lame excuse. iMessage is end to end encrypted and is arguably one of the most pleasant to use messengers.
Apple is very explicitly and deliberately building their systems to forcibly collect massive amounts of user data that they can and do provide to the federal government.
While it is true that close to all companies will comply with lawful orders (but not EVERY company, FWIW: Lavabit famously shut down instead of handing over SSL keys to feds), it is possible to design systems in such a way as to protect FAR more user data privacy than Apple does. Case in point: review the contents of Signal's subpoena response a few years ago:
This isn't a sham privacy claim like the kind made by Apple that requires you to trust the provider, either. Signal's clients are famously open source - something Apple does not do for pretty much any part of iOS or Mac OS:
Additionally, most of the Signal server's source code (nix the anti-spam components) is open source, as well as the libsignal library used across the clients and server alike:
Apple could be this transparent if they wanted to. They choose not to be, because the truth is, they do not actually care about user privacy, they are constantly collecting massive amounts of telemetry, user data, and user metadata from every single device they make, and they have been proven to share this data extensively with the federal government via the Snowden leaks, even in spite of the few actions they take publicly to maintain the marketing illusion of being a company that cares about user privacy, such as in the wake of the San Bernardino shooting.
Why is Apple taking the harder route then? Like having Maps go through proxies and get the route in small bits so that Apple's servers don't know who is going where, for example?
Meanwhile Google is giving you notifications about "would you like to review <this exact tiny shop you were just in>", because they are the good guys?
The TSA performs security theater, where they take the harder route, yet fail to even detect, let alone stop 95%+ of yesterday's threats, to say nothing of today's or tomorrow's threats:
As for the deeper why: it's more important to the US government for passengers to feel safe than it is for passengers to actually be truly safe.
Likewise, it's more profitable for Apple to make its customers feel their data is private than it is for Apple to make their customers data actually be truly private.
Apple is not privacy-preserving company.
Apple is marketed as a privacy-preserving company.
Again, you're just trusting Apple not to do that. Please bear in mind that if the government asks, it's not like they have a choice.