This'll have virtually no effect on trans women, who already weren't competing in the Olympics (in the more than 20 years in which trans women could participate in the Olympics, a grand total of... 1 actually made a team. She came in dead last in her event).
However....
apnews.com/article/ioc-...
Transgender women athletes ban...
Transgender women athletes ban...

Transgender women athletes banned from Olympics female events by IOC
Transgender women athletes are now excluded from the Olympics after the IOC agreed to a new eligibility policy It aligns with U.S. President Donald Trump’s executive order on women's sports ahead of the 2028 Los Angeles Games. The International Olympic Committee says “eligibility for any female category event at the Olympic Games or any other IOC event, including individual and team sports, is now limited to biological females.” Eligibility will be determined by "a one‑time SRY gene screening.” It is unclear how many, if any, transgender women are competing at an Olympic level.