It's just easier.
- I don't worry about not getting the latest updates (I know I will for at least 5-6 years)
- I don't worry about having infinite customization and needing to make my OS look "perfect" because iOS is very limited (personally in a good way)
- I don't have to worry as much about vulnerabilities (I know they do exist on iOS but they're far less than Android)
- I don't have to worry about my phone getting slow in only 2 years time
It's just easier on iPhone. More often than not, it truly does "just works".
I was on android for 6 years and in that time I've owned 3 phones because the damn things would slow down horribly after 2 years of use (and these were flagships as well). Every year I would worry if my phone would get the latest Android update or for how long it would be supported in general for. The infinite customization actually got annoying after a while because it's one of those things where if it's there, you might as well use it so I felt obligated to customize my phone in some manner every now and then. Apps were inconsistent in performance or in design continuity. The list goes on.