"We have shown that under testosterone suppression regimes typically used in clinical settings, and which comfortably exceed the requirements of sports federations for inclusion of transgender women in female sports categories by reducing testosterone levels to well below the upper tolerated limit, evidence for loss of the male performance advantage, established by testosterone at puberty and translating in elite athletes to a 10–50% performance advantage, is lacking."
Women (1:53,28 min):
https://de.wikipedia.org/wiki/Jarmila_Kratochv%C3%ADlov%C3%A...
Men (1:40,91):
https://de.wikipedia.org/wiki/David_Rudisha
At the time of her world record, Kratochvílová basically looked like a man (draw your own conclusions about doping).
So I find it very hard to believe that a male record holder would drop below her record just by taking hormones.