Earlier quoted context omitted.
The biggest reason for me using Android is simply because of how much competition there is in the space. If I use Apple products and don't like something they do then I'm stuck on an older version at best and need to migrate everything from their walled garden (at great cost) at worst. With Android, I can use Samsung one generation, switch to Pixel the next, and give Motorola/some other smaller company a chance later…
What would be the “great cost” of moving from an iPhone to an Android phone? I’m struggling to think of what would cost money at all, aside from the phone itself.
It's not just about migrating the phone, if you own an Apple Watch, AirPods, one of their laptops, their online services, etc. all that stuff works best within the Apple ecosystem. If you move they don't work as well (if at all) and you may need to replace them. If you are deeply bought in to Apple products, it really isn't that easy to move.