Interests and choices must come from somewhere. From personal preferences? Then where do preferences come from? Society and culture and family? Why would you bother to listen to the voice of society unless it resonated with your preferences?
Indeed, gay teenagers endure harsh and negative social criticism, but that doesn't persuade them to change. For the rest of us, it's just a coincidence that our preferences are socially accepted, even as we falsely attribute this coincidence to our strong moral character and willpower.
No, ultimately, our interests and choices boil down to Biology. Yet biology doesn’t determine outcomes. It merely constrains the set of possibilities. An elevator can bring you to any number of different floors. Which floor is not predetermined. But the elevator can't drive you across town.
Freedom of choice is another way of saying you choose according to your design. (Design is just another word for Biology.) Like an elevator that chooses to go up and down, functioning according to your design is the very essence of free choice. It's being who you are.
Being "born that way" refers only to being born with a certain developmental plan. Biology operates over time. A girl is not born with breasts - they arrive later - yet breast development is certainly biological. Development is not necessarily one way, either. The script (the programming) is what’s biological. But like a computer program, the script can be full of loops and conditionals.
The brain itself is constructed by a biological script (or rather a set of specialized scripts), thus what we can learn is constrained by what we’re hardwired to learn. We humans can learn language, but dogs can't, because they lack the biological script to properly wire their brain.
Biology has an internal state. The brain is the best example. We remember things, and this “state” (a memory of things past) becomes part of our current environment. It affects the outcome of our choices (which button on the elevator gets pushed).
Our interests, wants, needs, desires, etc, are coded into the brain, and vary based on our Biology, i.e. variations in our genes. Different people have different scripts. That's why people differ in their preferences, traits and capabilities.