“Say a boat with all strangers is sinking that you have nothing to do with or even know who anyone is, for example. Or any situation where between two people you have nothing other than the kedima stated in halacha.”
There has not been a case in the past 100 years I am aware of where a man was saved over a woman and the woman was left to drown or a yisroel was saved before a convert because of any halacha. Not one case. If there has been a case please tell me I would sincerely like to know.