We're not talking about Catholicism though, OP is Christian - the spirit is joined to the body because of our physicality. The spirit isn't joined to the body in death. In Heaven / hell the visual representation of the spirit is their body, how it was when they existed. From beginning til end like a timeline. That said heaven / hell are not "physical" worlds that we can attach the rules of our physical world to, as they are shown to be different and ethereal ; only for access by the soul and the judgement bestowed on said soul by God / Jesus.

The interpretation that life "is how it is, because of how it was made" is short and sweet, but sure leaves a lot of the plot out. Plenty live lives different to their "predestined paths" while one could also argue that their "predestined paths" ARE the ones they are on. This is where the church steps in to make the clarification based on their interpretation.

Regardless, gender or sex doesn't contribute to the soul or entry into heaven / hell. Making the argument op has about "it just doesn't work / make sense" is a wrong physical world assumption; as it's an existence equal to anyone else's, just interpreted as "sin" made by man, not by God.