None of those are the best product in their category, and all are only huge sellers because Apple anti-competitively privileges them in its ecosystem.
And since iPhones form the largest single company's device network in the rich countries, that is a pretty big advantage.
In your other thread you mentioned people don't necessarily want iPhones but they buy them to not be excluded from iMessage. I think you vastly underestimate how much regular people want low-bullshit tech experiences and are willing to pay for that.