Oddandelsewhere I thought your DC were in the City.
Strong Oxbridge medical graduates have better odds. Their achievements of getting through 6 years of medical school, including the sixth academic year, plus the resilience/communication and other skills gained during foundation have value.
Health is an important sector for the financial industry. Attractive to recruit people who have experience from the inside. Law firms too, are interested in recruiting those with medical experience, for much the same reason.
Many sough after careers involve competition and long hours. I don't think banking is that much worse than the sort of hours demanded of early career doctors. Before going home to study for the exams (often with 40% pass rates) and sort out the various CV enhancements required to get on training in the first place.
DD went to a central London private school where about 50% went on to Oxbridge. Most of her peers are forging good careers in finance, law, tech and elsewhere. And earn a lot more than her. Whereas she is not the only medic who, despite strong intercalations, in finding her career grinding to a halt.