Source?
> Late last year Dr. Jane Thornton, the I.O.C.’s medical and scientific director and a Canadian former Olympic rower, presented the initial findings of a review of athletes who are transgender or have differences of sexual development, known as DSD, and are competing in women’s sports. That analysis, which has not been made public, stated athletes born with male sexual markers retained physical advantages, including among those that had received treatment to reduce testosterone.
Let's be a little science-focused, okay?
So much for science.
Taking one stat which is uncontroversial. AFAB women are are significantly more likely to sustain ACL injuries than men or trans-women: https://pmc.ncbi.nlm.nih.gov/articles/PMC4805849/
Multiple reasons, but leg placement on the hip means direction change at pace puts more stress on joints, and the cycle appears to cause problems for reasons that AFAIK are still unknown.
It wouldn't shock me if some sports are impacted, but I also know that there are some vocal people on both sides of the opinion that would scream regardless of the outcome.
However we have examples like Ellia Green who, if we used "conventional wisdom" wouldn't have won in the mens Rugby Olympics. The one thing I've learnt is that things that sound important rarely are.