Headline is inaccurate.

Transgender athletes are not barred from women's events. Female athletes who identify as men, or otherwise do not identify as women, can still compete in this category, as they have been doing already.

What the IOC's new policy actually does is make male athletes ineligible for competition in the female category, with very few exceptions. These exceptions are for athletes who are technically male but have a disorder of sex development that confers no male advantage, e.g. CAIS.