Its difficult to think different if you're the world's largest company and dominate the phone market. In laptops it looks like they are differentiating themselves very well.
replies(2):
Debatable. If anything, modern Android designs are cleaner than iPhone looks.
> aesthetics
Again, debatable.
> and, most importantly, profit margin
This is the key factor, and it's tied to something you missed.
Apple products and iPhones are ahead in profit margins because Apple consistently delivers reasonable quality goods, with few disappointments, so that users trust them. They've gained user trust despite obvious "design, aesthetics" mis-steps such as the notch or the touch bar.
The key words are: consistent delivery, reasonable quality and few disappointments. That's how they hook users in. Apple mostly delivers on time something very close to what they promised and that thing doesn't have catastrophic flaws. That's a much taller bar than you'd think, in the tech sector.
Design is about more than the way apps & interface looks. I recently switched from Android and the thing that most struck me is that iPhone usability is more consistent. I was able to do everything I wanted with Android and honestly I loved it, but its not as intuitive as iOS.
One is iOS's arbitrary separation of settings and other app functionality. It makes no sense. I'll never remember what goes where.
Secondly, Android's back button is simple. I can use it without thinking even though you can probably find a lot of inconsistencies in its behaviour. iOS has multiple inconsistent one-off solutions for going back that cause a lot more mental friction.