46. The legislative findings for H.B. 500 contend that even after receiving gender-affirming hormone therapy, women and girls who are transgender have “an absolute advantage” over non-transgender girls. This assertion is based on speculation and inferences that have not been borne out by any evidence.
47. First, these arguments overlook the population of transgender girls and women who, as a result of puberty blockers at the start of puberty and gender affirming hormone therapy afterward, never go through a typical male puberty at all. These girls never experience the effects of high levels of testosterone and accompanying physiological changes. They go through puberty with the same levels of hormones as other girls and develop typically female physiological characteristics, including muscle and bone structure. Idaho’s law would bar them from participation in female athletics with absolutely no medical or scientific basis even based on the standards set forth in the legislative findings. ...
48. The legislative findings also state that “benefits that natural testosterone provides to male athletes is not diminished through the use of puberty blockers and cross-sex hormones.” This is not true. As noted above, puberty blocking treatment completely blocks the production of testosterone and someone who has undergone both puberty blocking treatment and then gender affirming hormone therapy to initiate puberty consistent with gender identity would have none of the impacts of testosterone on the body that would be typical for a non- transgender male. It is also not true that gender-affirming therapy – even for those who have not undergone puberty blocking treatment – does nothing to minimize the impact of testosterone on the body. In fact, consistent use of testosterone blockers and estrogen has a significant impact on the body.
49. The legislative findings also note that “Men generally have ‘denser, stronger bones, tendons, and ligaments’ and ‘larger hearts, greater lung volume per body mass, a higher red blood cell count, and higher hemoglobin” and suggest that such characteristics lead to athletic advantage and cannot be altered by sustained gender-affirming hormone therapy. However, the noted higher red blood cell count and higher hemoglobin are both testosterone dependent. They are both reduced as part of sustained gender-affirming hormone therapy. And there is currently no evidence that the remaining noted physiological characteristics actually are advantages when not accompanied by high levels of testosterone and corresponding skeletal muscle.

Edit to the edit: More

For example, the fact that transgender women who go through typically male puberty will tend to have larger bones than non-transgender women may actually be a disadvantage. Having larger bones without corresponding levels of testosterone and muscle mass would mean that a runner has a bigger body to propel with less power to propel it.
54. Similarly, in a sport where athletes compete in different weight classes (e.g. weight lifting), the fact that a transgender woman has bigger bones may be a disadvantage because her ratio of muscle-to-bone will be much lower than the ratio for other women in her weight class who have smaller bones

Edit to the edit to the edit: I see what happened, I got to the comment after it had been edited and OP put in the expert testimony. Removing snark but leaving in quotes. Good on you for changing your mind.