Yes and because of Linux’s “openness” it’s being used by most people as their main desktop OS and in the US 60% of the market are buying iPhones. Have you thought that their priorities aren’t the same as yours?

I'm not sure what you're trying to say.

I’m saying that

A) most people don’t care about openness based on their revealed preference

B) if you do care, you are free to choose a more “open” choice

Surely most people care at least enough about openness to want to be able to install apps on their phone. Your threat model is considering an authorized user installing an app to be a security breach.