This image of two human hip bones show why it is so important to know your own body and not compare ability to access a posture to anyone else. The one on the left is more open so that person would have been genetically more predisposed to greater external rotation of the femur on the hip socket. The person on the right might never be able to match the one on the left no matter how much they practiced or tried.
Photos from Paul Grilley yin yoga master teacher
No two pelvic girdles are alike. Respect what you’ve got!