Besides the fact that consumers aren't as rational as your question seems to imply, some of the reasons for the iPhone's dominance are the same reasons Apple are getting sued.

Marketing - android devices were notoriously janky in their beginning.

The vast majority of Android devices still are.

You can buy an "Android" phone, use it until EOL (no OS updates), get a new "Android" phone and it's a 100% different experience UI-wise and even the buttons are in different places.

Tinkerers love it, normal users just want a phone that works the same as the previous one.

The Apple ecosystem is part of what you're buying with an iPhone. As a consumer, I really like that I can buy a MacBook, an iPhone, and AirPods, and have them all work seamlessly together because they were designed to do so. I'm even willing to pay extra for each product to ensure that they work together in concert, as well as a subscription for a service (iCloud) that glues them all together.

Because a phone is not just a battery and a camera?