I learned iOS myself, and I know it would be harder for me if I didn't learn different flavors of programming languages and basic data structures at school.
I don't know how good people are at evaluating the usefulness of knowledge and skills they've acquired, but I'd believe there is some kind of bias. I tend to think things I know are trivial and can be learned easily. But I've also seen smart but non-CS background people cobbling poorly written code together only to make it work and he wished he has taken some CS classes while at school as well.
It might be true that smartest people can learn everything on their own, but by definition 'most people' aren't the smartest.
I don't know how good people are at evaluating the usefulness of knowledge and skills they've acquired, but I'd believe there is some kind of bias. I tend to think things I know are trivial and can be learned easily. But I've also seen smart but non-CS background people cobbling poorly written code together only to make it work and he wished he has taken some CS classes while at school as well.
It might be true that smartest people can learn everything on their own, but by definition 'most people' aren't the smartest.