"On the flip side of the argument, pretending that allowing trans athletes, even as regulated as they are to compete alongside their cis peers is “unfair,” and “ruining sports” is a massive oversimplification of the issue."
Problem here is that you've just made two entirely different arguments.
"Ruining" is hyperbole. Obviously, there are so few trans athletes that its entirely possible that a woman can compete from youth to college and not encounter one.
"Unfair" however, is a different matter. Because the moment a woman DOES encounter one in a competition, it becomes entirely unfair. For quite a few reasons. But reality is that (a) although testosterone repression to female norms can occur relatively quickly, it takes years before the athletes muscles weaken to female levels, and (b) skeletal and cardiovascular advantages do not abate with testosterone repression, and will always remain “male” for the purposes of comparison.
Key point here: You write "Basically, by the time you've been on hormones (...), you've lost all your testosterone-built muscles."
This is false. What the individual has done is lowered their testosterone level. The strength that's been built is lost at a much slower rate. Studies show that even 5 years after testosterone normalization to females levels, male advantages persist.
https://link.springer.com/article/10.1007/s40279-020-01389-3
Returning to the subject of skeletal advantage - you're minimizing something which is significant. Male joints articulate at angles which facilitate speed and strength; female joints articulate at angles which facilitate childbearing. Then, there is the physics of levers. Again, the relative length of male bones (the levers) around the joints (the fulcrum) is optimized for speed and strength; this is not true of the female.
Further, the Michael Phelps argument is a red herring. Yes, Phelps possessed skeletal advantages which optimized his abilities in the pool; however, his records have been broken by the very normal sized and proportioned Caleb Dressel; In the 1980’s, the German Michael Gross possessed the same sorts of proportions as Phelps, leading to his own dominance in the same events; those times today would not even make an Olympic final. So yes, these physical aberrations occur from time to time, but they are transitory; the vast majority of Olympic winners do not possess any sort of unusual physical advantages.
Further, you would be interested to know, I think, that in age group swimming, boys are faster than girls from the very beginning of their competitions; there are no age 10 and under world records where the boys time is slower than the girls time, even though that age is pre-puberty and girls are usually taller than boys are at that stage of development.
When you take all the data in total, it’s clear that in sport, we have a choice. We can be inclusive, or we can be fair to women and girl athletes; we cannot do both.
As for the argument that this is so rare that it cannot be unfair….please. Let’s take a look at a recent example, also in swimming, described by Abigail Shrier. This event occurred just this year, and reminds us that statistically, it's just a matter of time before this sort of even happens at the highest level in sport.
" I want you to think for a moment about a young woman here at Princeton. She’s a magnificent athlete named Ellie Marquardt, an all-American swimmer who set an Ivy League record in the 500-meter freestyle event as a freshman. Just before Thanksgiving, Ellie was defeated in the 500-meter, the event she held the record in, by almost 14 seconds by a 22 year old biological male at Penn who was competing on the men’s team as recently as November of 2019. That male athlete now holds multiple U.S. records in women’s swimming, erasing the hard work of so many of our best female athletes, and making a mockery of the rights women fought for generations to achieve."
"Ellie Marquart swam her heart out for Princeton. When will Princeton fight for her? Where are the student protests to say—enough is enough. When a biological male who has enjoyed the full benefits of male puberty—larger cardiovascular system, 40% more upper body muscle mass, more fast-twitch muscle fiber, more oxygenated blood—decides after three seasons on the men’s team to compete as a woman and smashes the records of the top female swimmers in this country, that is not valor—that’s vandalism."
"Where is the outrage? Imagine, for a second, what it must be like to be a female swimmer at Princeton, knowing you must pretend that this is fair—that the NCAA competition is anything other than a joke. Imagine being told to bite your tongue as men lecture you that you just need to swim harder. “Be grateful for your silver medals, ladies, and maybe work harder next time,” is the message. Imagine what that level of repression does to warp the soul."
Respectfully, I suggest you rethink your original premise.
