Interesting but sadly not a unique case (haven't got my Feb. National Masters news yet to read the source article) and likely many more out there.
Beyond documented primary hypogonadism, age-related hormonal level decline and especially the "Low T" syndromes are coming under increasing scrutiny eg if you have a "real" low T how much physiologic replacement do you need before overdrive and then advantage kick in? And what about the risks (eg CV, hepatic, prostatic etc) associated with replacement?
A sad end to an elite career, however this guy (Ryan Hall) made the right choice:
Personally I am glad that this never came up as a conssideration for me, otherwise I would be not be sitting where I am wrt early stage curable Prostate Cancer!