It's an interesting one. Considering that the athlete competed as a junior I assume she also tried to get in to the Olympic team prior to her transition but was unsuccessful. Now she is ranked 4th in the world for her division. As I see it there's only two possible reasons for her current success despite being 43. That transitioning has not nullified all advantages or that the number of women weightlifters is lower and thus less competitive. Most likely some combination of the two.

Another interesting aspect is that New Zealand now has a much better chance to get a medal in this event. Given the importance that some countries give to winning the games, e.g China and Russia, might they push to have more MtF athletes of their own.