BTD is granted to clinical-stage drugs that provide a substantial benefit over SOC (approved therapies).

What Nader said was "we haven't done that", meaning leronlimab hasn't shown a substantial improvement over the approved SOC, sacituzumab. So he didn't refer to a winner take all scenario, he specifically said that leronlimab hasn't proven itself to be clearly superior yet, and that results since the BTD was submitted are very positive. There is still the possibility of another BTD submission as time goes on and leronlimab hopefully shows larger quantifiable increases in survivability and an obvious improvement over sacituzumab.