He explicitly referred to Fallon Fox, saying "You are a fucking man." Not a very tactful way to speak about a transgender woman. And yes, that's transphobic speech.
So? "you are a fucking man" isn't some dispassionate analysis of how to develop a rule system that works for both trans and cis athletes. Just because the context isn't inherently transphobic doesn't mean that he gets a free pass.
He doesn't need a "free pass". The context and what he was saying was crystal clear and has nothing to do with disrespecting someone who is transgender.
This person was able to brutalize women because of attitudes like yours, where you are too afraid of using the incorrect pronoun even in the context of making a point about dangerous differences in physicality.
This person beat a woman until her skull cracked and you are hung up on someone saying she has the physiology of a man. What do you think sets the acceptance of transgender people back more?