I'm not sure how the considered wisdom of shepherds from three millennia ago or so is relevant here. This wasn't exactly a common occurrence back then (though there were very rare genetic abnormalities that even then would have shown that people are only almost always either men or women morphologically).

Regarding people transitioning and demolishing records: yes, that's clear evidence that whatever the requirements were in that particular instance were likely insufficient.

You can't go from anecdotes like that to a general policy unless...ta-da!...you do science. Does duration of transition matter? Does muscle mass matter? Do the skeletal differences (which don't change) impact this sport significantly? Etc..