At the general level, you pose an interesting question, but at the specific level – the question of birth control – it’s not tied to traditionalism at all. Pope Paul VI, in Humanae Vitae, upheld traditional Church teaching that birth control is wrong (eg: a mortal sin). If you don’t assent to that then you’ve got your back to the Magisterium and one foot out of the Church (unless this has been infallibly defined, then you’re out of the Church altogether). This isn’t a question of spirituality but one of holding to Church teachings.
Perhaps your question should be significantly reworded?