It doesn't need to follow Windows or Android's UX, but it should be allowed.
Something like a settings menu where you can control the default apps for many "intents" (that's the android terminology, not sure what else to call it).
Choose an app for email, sms, "instant messaging", browser, navigation, phone, etc... Don't let individual apps change anything, and if you want don't even let them prompt you to change something. That last part can be enforced by appstore guidelines.
If apple does this, i'd switch overnight. And as someone that is about as far away from the apple ecosystem as you can be, i'd probably end up using many of the apple "things" over time. Let their first party apps stand on their own. I have no qualms with having theirs be the default, and it honestly doesn't even bother me if they aren't un-installable, but let me change my defaults!
Android asks once, right after a new app is installed that has the ability to be default handler for that action. There's a slight annoyance factor here, but its taken care of quickly and its a lot easier to see this menu pop-up than dig through settings to manually handle what app controls what.
Meanwhile on my ipad, I feel like Apple is making all the choices and I just have to deal with it. This is the biggest difference between Apple and Android for me. My Android devices have the apps I like and 'just work' when launched or whatever. Apple forcibly opens the Apple apps and I need to run down my screens of installed apps to find what I actually want to run.
I don't know how in this day and age I can't choose my default handlers of a product I own.
On Android I can make a new email client, and overnight it can become the default email client for everyone that installs it.
On iOS I would need to convince most large apps to allow me as an option before it would work.
Not being able to do this is basically the last thing keeping me off of iOS at this point.