Not sure I agree that conservatives can both “choose” to be like they are, and also be the victims of their upbringing in a toxic system. These 2 points you made seem to be contradictory.

Not really.

We are all subjected to the same propaganda, yet we're not all conservatives, that's enough to prove that there is choice involved (even if the choices are limited, and opinions externally influenced by and for the ruling class), but more to the point - no one is born conservative, and no one is forced in any way to support one political party or another, political affiliation isn't something someone can't help or control or change, making it a choice, unlike race, gender, sexual orientation, abledness, place and circumstances of birth, and so on, which are not.